Distribution by Scientific Domains
Distribution within Chemistry

Kinds of Ordering

  • antiferromagnetic ordering
  • cation ordering
  • charge ordering
  • ferromagnetic ordering
  • long-range ordering
  • magnetic ordering
  • molecular ordering
  • orbital ordering
  • orientational ordering
  • partial ordering
  • rank ordering
  • social ordering
  • stochastic ordering
  • structural ordering

  • Terms modified by Ordering

  • ordering process
  • ordering scheme

  • Selected Abstracts


    We study how an updated demand forecast affects a manufacturer's choice in ordering raw materials. With demand forecast updates, we develop a model where raw materials are ordered from two suppliers,one fast but expensive and the other cheap but slow,and further provide an explicit solution to the resulting dynamic optimization problem. Under some mild conditions, we demonstrate that the cost function is convex and twice-differentiable with respect to order quantity. With this model, we are able to evaluate the benefit of demand information updating which leads to the identification of directions for further improvement. We further demonstrate that the model applies to multiple-period problems provided that some demand regularity conditions are satisfied. Data collected from a manufacturer support the structure and conclusion of the model. Although the model is described in the context of in-bound logistics, it can be applied to production and out-bound logistics decisions as well. [source]


    Miguel López-Díaz
    Summary A new univariate stochastic ordering is introduced. Some characterization results for such an ordering are stated. It is proved that the ordering is an integral stochastic ordering, obtaining a maximal generator. By means of this generator, the main properties of the ordering are deduced. A method for introducing univariate stochastic orderings, suggested by the new ordering, is analysed. Relationships with other stochastic orderings are also developed. To conclude, an example of an application of the new ordering to the field of medicine is proposed. [source]


    We examine the optimal R&D subsidy/tax policy under a vertically differentiated duopoly. In a significant departure from the existing work, we consider the case of asymmetric costs of product R&D where there is a small technology gap between firms. In our analysis, the endogeneity of quality ordering is explicitly taken into account. We demonstrate the possible anti-leapfrogging effect of R&D subsidy/tax policy. By committing to a firm-specific subsidy schedule contingent on firms' quality choices, the government can not only correct distortions in product quality but also select the socially preferred equilibrium. The latter role is fulfilled by preventing the technologically inferior firm from becoming a quality leader in the industry. Both Bertrand and Cournot cases are analysed. [source]

    Hierarchical Context-based Pixel Ordering

    Ziv Bar-Joseph
    Abstract We present a context-based scanning algorithm which reorders the input image using a hierarchical representationof the image. Our algorithm optimally orders (permutes) the leaves corresponding to the pixels, by minimizing thesum of distances between neighboring pixels. The reordering results in an improved autocorrelation betweennearby pixels which leads to a smoother image. This allows us, for the first time, to improve image compressionrates using context-based scans. The results presented in this paper greatly improve upon previous work in bothcompression rate and running time. Categories and Subject Descriptors (according to ACM CCS): I.3.5 [Computer Graphics]: Computational Geometryand Object Modeling I.3.6 [Computer Graphics]: Methodology and Techniques [source]

    Partial Ordering of Unpredictable Mobility with Welfare Implications

    ECONOMICA, Issue 299 2008
    We propose a partial ordering of ,unpredictable mobility' in the spirit of Blackwell's ordering of information structures. The proposed ordering ranks mobility matrices according to the degree to which elements in a given set are likely to move from one state to another, independently of their origin. Furthermore, for an important class of transition structures, our proposed ordering implies ordering, thus carrying significant welfare implications. Moreover, whenever it exists, our partial ordering functions as a sufficient condition for a class of renowned mobility measures and thereby generates, for a subset of transition matrices, unanimous ranking among mobility indices that are not generally consistent with one another. [source]

    Ordering of Disordered Nanowires: Spontaneous Formation of Highly Aligned, Ultralong Ag Nanowire Films at Oil,Water,Air Interface

    Hong-Yan Shi
    Abstract One-dimensional nanomaterials and their assemblies attract considerable scientific interest in the physical, chemical, and biological fields because of their potential applications in electronic and optical devices. The interface-assembly method has become an important route for the self-assembly of nanoparticles, nanosheets, nanotubes, and nanorods, but the self-assembly of ultralong nanowires has only been successful using the Langmuir,Blodgett approach. A novel approach for the spontaneous formation of highly aligned, ultralong Ag nanowire films at the oil,water,air interface is described. In this approach, the three-phase interface directs the movement and self-assembly process of the ultralong Ag nanowires without the effect of an external force or complex apparatus. The ordered films exhibit intrinsic large electromagnetic fields that are localized in the interstitials between adjacent nanowires. This new three-phase-interface approach is proven to be a general route that can be extended to self-assemble other ultralong nanowires and produce ordered films. [source]

    Multifunctional Microporous MOFs Exhibiting Gas/Hydrocarbon Adsorption Selectivity, Separation Capability and Three-Dimensional Magnetic Ordering,

    Kunhao Li
    Abstract Microporous materials [M3(HCOO)6],·,DMF (M,=,Mn, Co, Ni) were synthesized solvothermally and structurally characterized by single crystal and powder X-ray diffraction methods. The metal network exhibits diamondoid connectivity and the overall framework gives rise to zigzag channels along the b axis where guest dimethylformamide molecules reside. The effective pore size of these channels is ,5,6,Å. The materials feature high thermal stability and permanent porosity with relatively small pore diameters which are attributed to the extensive strong dative bonding between the metal centers and formate molecules. The title compounds exhibit interesting multi-fold gas adsorption and magnetic properties. The adsorption study of a series of alcohols, aromatics, and linear hydrocarbons revealed strong control of the adsorbent channel structures on their adsorption capacity and selectivity. The study also indicated possibility of using these materials for separation of close boiling chemicals (e.g., ethylbenzene and p-xylene) via pressure swing adsorption (PSA) process and molecules with different diffusion parameters via kinetic-based process. Three-dimensional spontaneous magnetic ordering was found in all three network structures investigated and at ground states they behave somewhat like soft magnets. [source]

    2,7-Carbazolenevinylene-Based Oligomer Thin-Film Transistors: High Mobility Through Structural Ordering,

    N. Drolet
    Abstract We have fabricated organic field-effect transistors based on thin films of 2,7-carbazole oligomeric semiconductors 1,4-bis(vinylene-(N -hexyl-2-carbazole))phenylene (CPC), 1,4-bis(vinylene-(N,-methyl-7,-hexyl-2,-carbazole))benzene (RCPCR), N -hexyl-2,7-bis(vinylene-(N -hexyl-2-carbazole))carbazole (CCC), and N -methyl-2,7-bis(vinylene-(7-hexyl- N -methyl-2-carbazole))carbazole (RCCCR). The organic semiconductors are deposited by thermal evaporation on bare and chemically modified silicon dioxide surfaces (SiO2/Si) held at different temperatures varying from 25 to 200,°C during deposition. The resulting thin films have been characterized using UV-vis and Fourier-transform infrared spectroscopies, scanning electron microscopy, and X-ray diffraction, and the observed top-contact transistor performances have been correlated with thin-film properties. We found that these new ,-conjugated oligomers can form highly ordered structures and reach high hole mobilities. Devices using CPC as the active semiconductor have exhibited mobilities as high as 0.3,cm2,V,1,s,1 with on/off current ratios of up to 107. These features make CPC and 2,7-carbazolenevinylene-based oligomers attractive candidates for device applications. [source]

    Molecular Ordering of High-Performance Soluble Molecular Semiconductors and Re-evaluation of Their Field-Effect Transistor Characteristics,

    ADVANCED MATERIALS, Issue 18 2008
    Takafumi Izawa
    Intermolecular hydrophobic interactions between long alkyl chains (fastener effect) can enhance the intermolecular overlap of the semiconducting layer of 2,7-dialkyl[1]benzothieno[3,2- b][1]benzothiophenes (Cn -BTBTs; n,=,8, 10, 12), which contributes to improvements of the electric characteristics of their organic field-effect transistors. The molecular ordering of Cn -BTBTs in the thin-film state is elucidated by means of in-plane and out-of-plane X-ray diffraction of spin-coated thin films, and single crystal X-ray analysis. [source]

    Study of Cation Ordering in Ba(Yb1/2Ta1/2)O3 by X-Ray Diffraction and Raman Spectroscopy

    Dibyaranjan Rout
    The complex perovskite Ba(Yb1/2Ta1/2)O3 has been prepared by the two-stage solid-state reaction method. Rietveld' refinement analysis indicates cubic perovskite phase with space group . The 1:1 cation ordering at the B-site is revealed by the presence of (111) superlattice reflection in the X-ray diffraction pattern and further evidenced by the presence of A1g and F2g vibrational modes in the Raman spectra. The dielectric constant is measured to be 29.1, the product of quality factor and resonant frequency (Q×f) is found to be 32,000 GHz and the temperature coefficient of resonant frequency (,f) is 135 (ppm/°C) in the temperature range 30,70°C. [source]

    Advantageous 3D Ordering of ,-Conjugated Systems: A New Approach Towards Efficient Charge Transport in any Direction,

    ADVANCED MATERIALS, Issue 24 2007
    H. Pang
    A new organic semiconductor based on a benzobisthiazole core has been studied as a hole transport material in field effect transistors; remarkably, the material self-assembles in the solid state to give intermolecular short contacts in all three dimensions. [source]

    Spontaneous Vertical Ordering and Pyrolytic Formation of Nanoscopic Ceramic Patterns from Poly(styrene- b -ferrocenylsilane),

    ADVANCED MATERIALS, Issue 4 2003
    K. Temple
    The rapid generation of nanopatterned surfaces using thin films of the amorphous diblock copolymer poly(styrene- b -ferrocenylethylmethylsilane) (PS- b -PFS) is reported. Spontaneous self-assembly into vertically oriented cylinders of PFS in a PS matrix is observed on a variety of substrates by spin or dip coating, irrespective of the substrate surface polarity. Pyrolysis of the films affords arrays of 20 nm Fe-containing ceramic nanoparticles, (see Figure, AFM, 4 ,m2 scan area). [source]


    ABSTRACT The goal in a multi-objective function optimization problem is to optimize the several objective functions simultaneously. the complex method is a powerful algorithm to find the optimum of a general nonlinear function within a constrained region. the objective of this study was to apply the complex method to two different shapes (a sphere and a finite cylinder) subjected to the same thermal processing boundary conditions to find a variable process temperature profile (decision variable) to maximize the volume-average retention of thiamine. A process temperature range of 5 to 150C was used as an explicit constraint. Implicit constraints were center temperature and accumulated center lethality of the sphere and the finite cylinder. the objective functions for both shapes were combined into a single one using a weighting method. Then, the previously developed complex algorithm was applied using Lexicographic Ordering to order the objective functions with respect to their significance. the results were reported as optimum variable process temperature profiles using the given geometries and objective functions. the thiamine retentions were also compared with a constant process temperature process, and 3.0% increase was obtained in the combined objective function. the results showed that the complex method can be successfully used to predict the optimum variable process temperature profiles in multi-criteria thermal processing problems. [source]

    Cation Ordering and Domain Boundaries in Ca[(Mg1/3Ta2/3)1,xTix]O3 Microwave Dielectric Ceramics

    Mao Sen Fu
    Cation ordering and domain boundaries in perovskite Ca[(Mg1/3Ta2/3)1,xTix]O3 (x=0.1, 0.2, 0.3) microwave dielectric ceramics were investigated by high-resolution transmission electron microscopy (HRTEM) and Rietveld analysis. The variation of ordering structure with Ti substitution was revealed together with the formation mechanism of ordering domains. When x=0.1, the ceramics were composed of 1:2 and 1:1 ordered domains and a disordered matrix. The 1:2 cation ordering could still exist until x=0.2 but the 1:1 ordering disappeared. Neither 1:2 nor 1:1 cation ordering could exist at x=0.3. The space charge model was used to explain the cation ordering change from 1:2 to 1:1 and then to disorder. A comparison between the space charge model and random layer model was also conducted. HRTEM observations showed an antiphase boundary inclined to the (111)c plane with a projected displacement vector in the ,001,c direction and ferroelastic domain boundaries parallel to the ,100,c direction. [source]

    Cation Ordering and Dielectric Characteristics in Barium Zinc Niobate

    Chun-Te Lee
    Barium zinc niobate (Ba(Zn1/3Nb2/3)O3) (BZN) complex perovskite has been reported to have special microwave dielectric properties with close relation of its ordered structure. This study investigated the effect of calcination on the evolution of ordered structure and on quality factor with Raman spectroscopy, X-ray diffractometry, and transmission electron microscopy. The results revealed that single calcination at a lower temperature inhibited the growth of the ordered domain during sintering. In contrast, the 1:2-ordered domain in double-calcined BZN powder grew significantly with a higher sintering temperature and a longer soaking time. It is attributed that double calcination caused a higher degree of 1:2 ordering and better homogeneity. At the same time, the quality factor of the sintered ceramic body was highly promoted when using double-calcined powder. A close relation of the quality factor with the size of ordered domain, the degree of 1:2 ordering, and the relative density of BZN ceramics was presented. [source]

    Evidence of Nearest-Neighbor Ordering in Wet-Processed Zirconia,Nickel Composites

    Carlos Pecharromán
    Monolithic zirconia,nickel (ZrO2/Ni) cermets have been prepared by a wet-processing method with nickel volume concentrations of 16%,40%. Microstructural analysis performed on scanning electron microscopy images has revealed evidence of a partial ordering of metallic particles inside the ceramic matrix. This ordering does not appear in mullite/molybdenum cermets. Complex impedance measurements have shown that the percolation threshold of ZrO2/Ni cermets appears at a filling factor (fc) of 0.34, exceeding the theoretical value (fc= 0.16), as a consequence of its microstructural order. Electrical measurements display the expected increase of capacity near the percolation threshold. These results open the possibility to design new devices with the appealing electric, magnetic, and mechanical properties that are predicted by the percolation theory. [source]

    Synergistic Ordering of Side-Group Liquid Crystal Polymer and Small Molecule Liquid Crystal: Order and Phase Behavior of Nematic Polymer Solutions,

    Neal R. Scruggs
    Abstract Addition of a small-molecule liquid crystal (5CB) to a cyanobiphenyl-based side-group liquid crystal polymer (SGLCP) stabilizes nematic order, increasing the isotropization temperature (TNI) more than 15,°C. Despite synergistic ordering at high concentration, small amounts of polymer destabilize nematic order. Even though TNI(SGLCP) is 27,°C greater than TNI(5CB), 2H NMR shows that the order parameter of the SGLCP is less than that of 5CB at concentrations for which monodomains were accessible (,10 wt.-%). The results imply that nematic order is frustrated in the bulk polymer and addition of small molecule LC relaxes this frustration by allowing greater configurational freedom. Conversely, adding small amounts of polymer to the bulk 5CB introduces frustration, resulting in the strong asymmetry of the phase diagram. [source]

    Liquid Crystalline Ordering and Charge Transport in Semiconducting Materials

    Wojciech Pisula
    Abstract Organic semiconducting materials offer the advantage of solution processability into flexible films. In most cases, their drawback is based on their low charge carrier mobility, which is directly related to the packing of the molecules both on local (amorphous versus crystalline) and on macroscopic (grain boundaries) length scales. Liquid crystalline ordering offers the possibility of circumventing this problem. An advanced concept comprises: i) the application of materials with different liquid crystalline phases, ii) the orientation of a low viscosity high temperature phase, and, iii) the transfer of the macroscopic orientation during cooling to a highly ordered (at best, crystalline-like) phase at room temperature. At the same time, the desired orientation for the application (OLED or field-effect transistor) can be obtained. This review presents the use of molecules with discotic, calamitic and sanidic phases and discusses the sensitivity of the phases with regard to defects depending on the dimensionality of the ordered structure (columns: 1D, smectic layers and sanidic phases: 2D). It presents ways to systematically improve charge carrier mobility by proper variation of the electronic and steric (packing) structure of the constituting molecules and to reach charge carrier mobilities that are close to and comparable to amorphous silicon, with values of 0.1 to 0.7,cm2,·,V,1,·,s,1. In this context, the significance of cross-linking to stabilize the orientation and liquid crystalline behavior of inorganic/organic hybrids is also discussed. [source]

    Microscopic diagnostics of DNA molecules on mono-crystalline diamond

    Bohuslav Rezek
    Abstract Detailed data about deoxyribonucleic acid (DNA) attachment, arrangement, density and functionality on mono-crystalline diamond surfaces are obtained by direct measurements in electrolytic solutions using fluorescence microscopy and atomic force microscopy in various regimes (oscillating, contact, phase, and surface potential imaging) and by fitting the data into a microscopic geometrical model of DNA. DNA is immobilized on undoped and boron-doped diamonds with hydrogen and oxygen surface terminations which were functionalized by aminodecene and nitrofenyl linker molecules. The data show that, except photochemically processed oxidized diamond surfaces, the DNA molecules are covalently linked to diamond in a 65,92 Å thin and highly dense layers (6 × 1012 molecules/cm2) with sub-nanometer intermolecular spacing and a strong tilt of 31° with respect to the surface. Ordering of these DNA layers shows only a weak (<10%) response to a change of buffer salinity in the range of 1,300 mM. The data are discussed with view to biosensor applications. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

    Racial and Sex Differences in Emergency Department Triage Assessment and Test Ordering for Chest Pain, 1997,2006

    Lenny López MD
    ACADEMIC EMERGENCY MEDICINE 2010; 17:801,808 © 2010 by the Society for Academic Emergency Medicine Abstract Objectives:, This study assessed whether sociodemographic differences exist in triage assignment and whether these differences affect initial diagnostic testing in the emergency department (ED) for patients presenting with chest pain. Methods:,A nationally representative ED data sample for all adults (,18 years) was obtained from the National Hospital Ambulatory Health Care Survey of EDs for 1997,2006. Weighted logistic regression was used to examine the associations between race and presenting symptom, triage assignment, and test ordering, adjusting for patient and hospital characteristics. Results:, Over 10 years, an estimated 78 million visits to the ED presented with a complaint of chest pain. Of those presenting with chest pain, African Americans (odds ratio [OR] = 0.70; 99% confidence interval [CI] = 0.53 to 0.92), Hispanics (OR = 0.74; 99% CI = 0.51to 0.99), Medicaid patients (OR = 0.72; 99% CI = 0.54 to 0.94), and uninsured patients (OR = 0.65; 99% CI = 0.51 to 0.84) were less likely to be triaged emergently. African Americans (OR = 0.86; 99% CI = 0.70 to 0.99), Medicaid patients (OR = 0.70; 99% CI = 0.55 to 0.88), and uninsured patients (OR = 0.70; 99% CI = 0.55 to 0.89) were less likely to have an electrocardiogram (ECG) ordered. African Americans (OR = 0.69; 99% CI = 0.49 to 0.97), Medicaid patients (OR = 0.67; 99% CI = 0.47 to 0.95), and uninsured patients (OR = 0.66; 99% CI = 0.44 to 0.96) were less likely to have cardiac enzymes ordered. Similarly, African Americans and Hispanics were less likely to have a cardiac monitor and pulse oximetry ordered, and Medicaid and uninsured patients were less likely to have a cardiac monitor ordered. Conclusions:, Persistent racial, sex, and insurance differences in triage categorization and basic cardiac testing exist. Eliminating triage disparities may affect "downstream" clinical care and help eliminate observed disparities in cardiac outcomes. [source]

    La(Ni2/3Nb1/3)O3 by neutron powder diffraction

    Julian R. Tolchard
    Lanthanum nickel niobium trioxide has been synthesized and its structure refined for the first time. It was found to be a member of the family of technologically important `double perovskites', crystallizing in the monoclinic space group P21/n. The structure is characterized by a strong orthorhombic pseudosymmetry and a concurrent exhibition of both 1:1 B -cation ordering and a,a,c+ -type tilting of the (Ni/Nb)O6 structural units. Trivalent lanthanum resides on the perovskite A site, which is strongly distorted owing to the tilting of the (Ni/Nb)O6 sublattice. Ordering of divalent nickel and pentavalent niobium on the B sublattice is described in terms of two twofold special positions (2c and 2d), with nickel taking almost complete occupancy of the 2d site and the 2c position being occupied by a statistical distribution of nickel and niobium. [source]

    On some measures and distances for positive random variables

    M. S. FinkelsteinArticle first published online: 2 MAY 200
    Abstract A number of conventional measures of risk as real-valued functions on the space of positive random variables are considered: the expected shortfall, the mean excess over the threshold, the stop-loss and some others. Ordering of risks, based on these measures and the distances between corresponding distribution functions, are described. The perturbed measures, describing the effect of changing environment, are discussed. These measures are defined by the accelerated life and proportional hazards models widely used in reliability and survival analysis. The case of a random environment is of a prime interest in the paper. The main result states that if, for instance, the stochastic environment is ,neutral in expectation' with respect to the baseline one, the distance between the corresponding distribution functions can be still sufficiently large. Copyright © 2003 John Wiley & Sons, Ltd. [source]

    Testing a Partial Ordering of Population Means with Application to Inference about Growth Habits of Cowpea Genotypes

    BIOMETRICS, Issue 4 2007
    Daniel R. Jeske
    Summary Using general results available in the literature, we derive the likelihood ratio test for a particular partial ordering of means that naturally arises in a biological context. We then show that the conceptual and computational complexity of the derivation can be substantially reduced by equivalently deriving the test using the intersection-union principle for decomposing a complex null hypothesis into elemental forms. A Monte Carlo algorithm for obtaining the p -value of the test is proposed. The test procedure is illustrated with a data set of the competitive ability of several cowpea genotypes, where previous experiments have indicated the proposed partial order of the means. A simulation study is used to examine the power of the test. [source]

    ChemInform Abstract: Magnetic Ordering of the R4Sb3 Compounds (R: Pr, Nd, Sm) and of Pr2Nd2Sb3.

    CHEMINFORM, Issue 22 2010
    C. Ritter
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

    ChemInform Abstract: Platinum-Germanium Ordering in the Germanides REPtGe with the Heavy Rare Earth Elements.

    CHEMINFORM, Issue 28 2009
    Ute Ch.
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

    ChemInform Abstract: Ferromagnetic Ordering in CeZnSn.

    CHEMINFORM, Issue 19 2009
    Wilfried Hermes
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

    ChemInform Abstract: Coupled Spin Ordering in the Ln2LiRuO6 Double Perovskites.

    CHEMINFORM, Issue 17 2009
    Sophia J. Makowski
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

    ChemInform Abstract: Density Functional Theory Studies of Spin, Charge, and Orbital Ordering in YBaT2O5 (T: Mn, Fe, Co).

    CHEMINFORM, Issue 40 2008
    R. Vidya
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

    ChemInform Abstract: Partial Charge Ordering in the Mixed-Valent Compound (Bi6O5) Rh83+Rh44+O24.

    CHEMINFORM, Issue 24 2008
    H. Mizoguchi
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

    ChemInform Abstract: Coupled In/Te and Ni/Vacancy Ordering and the Modulated Crystal Structure of a B8 Type, Ni3.+-.xIn1-yTe2+y Solid Solution Phase.

    CHEMINFORM, Issue 22 2008
    A.-K. Larsson
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]