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<title>Whittaker function</title>
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<span id="openzim-page-title" class="mw-page-title-main"><span class="mw-page-title-main">Whittaker function</span></span>
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<p>In mathematics, a <b>Whittaker function</b> is a special solution of <b>Whittaker's equation</b>, a modified form of the <a href="Confluent_hypergeometric_equation" class="mw-redirect" title="Confluent hypergeometric equation">confluent hypergeometric equation</a> introduced by <a href="E._T._Whittaker" title="E. T. Whittaker">Whittaker</a>&nbsp;(<a href="#CITEREFWhittaker1903">1903</a>) to make the formulas involving the solutions more symmetric. More generally, <a href="Herv%C3%A9_Jacquet" title="Hervé Jacquet">Jacquet</a>&nbsp;(<a href="#CITEREFJacquet1966">1966</a>, <a href="#CITEREFJacquet1967">1967</a>) introduced Whittaker <a href="Function_(mathematics)" title="Function (mathematics)">functions</a> of <a href="Reductive_group" title="Reductive group">reductive groups</a> over <a href="Local_field" title="Local field">local fields</a>, where the functions studied by Whittaker are essentially the case where the local field is the real numbers and the group is SL<sub>2</sub>(<b>R</b>).
</p><p>Whittaker's equation is
</p>
<dl><dd><span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {\frac {d^{2}w}{dz^{2}}}+\left(-{\frac {1}{4}}+{\frac {\kappa }{z}}+{\frac {1/4-\mu ^{2}}{z^{2}}}\right)w=0.}">
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<annotation encoding="application/x-tex">{\displaystyle {\frac {d^{2}w}{dz^{2}}}+\left(-{\frac {1}{4}}+{\frac {\kappa }{z}}+{\frac {1/4-\mu ^{2}}{z^{2}}}\right)w=0.}</annotation>
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</math></span><img src="./104ed9bcd2df2d881882a8fa4abc48940e8bf67a.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -3.171ex; width:39.536ex; height:7.509ex;" alt="{\displaystyle {\frac {d^{2}w}{dz^{2}}}+\left(-{\frac {1}{4}}+{\frac {\kappa }{z}}+{\frac {1/4-\mu ^{2}}{z^{2}}}\right)w=0.}" loading="lazy"></span></dd></dl>
<p>It has a <a href="Regular_singular_point" title="Regular singular point">regular singular point</a> at 0 and an irregular singular point at ∞.
Two solutions are given by the <b>Whittaker functions</b> <i>M</i><sub>κ,μ</sub>(<i>z</i>), <i>W</i><sub>κ,μ</sub>(<i>z</i>), defined in terms of Kummer's <a href="Confluent_hypergeometric_functions" class="mw-redirect" title="Confluent hypergeometric functions">confluent hypergeometric functions</a> <i>M</i> and <i>U</i> by
</p>
<dl><dd><span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle M_{\kappa ,\mu }\left(z\right)=\exp \left(-z/2\right)z^{\mu +{\tfrac {1}{2}}}M\left(\mu -\kappa +{\tfrac {1}{2}},1+2\mu ,z\right)}">
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<annotation encoding="application/x-tex">{\displaystyle M_{\kappa ,\mu }\left(z\right)=\exp \left(-z/2\right)z^{\mu +{\tfrac {1}{2}}}M\left(\mu -\kappa +{\tfrac {1}{2}},1+2\mu ,z\right)}</annotation>
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</math></span><img src="./22b70e3592752abfaa97b52cfc841be84632938c.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.171ex; width:51.86ex; height:4.843ex;" alt="{\displaystyle M_{\kappa ,\mu }\left(z\right)=\exp \left(-z/2\right)z^{\mu +{\tfrac {1}{2}}}M\left(\mu -\kappa +{\tfrac {1}{2}},1+2\mu ,z\right)}" loading="lazy"></span></dd>
<dd><span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle W_{\kappa ,\mu }\left(z\right)=\exp \left(-z/2\right)z^{\mu +{\tfrac {1}{2}}}U\left(\mu -\kappa +{\tfrac {1}{2}},1+2\mu ,z\right).}">
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<annotation encoding="application/x-tex">{\displaystyle W_{\kappa ,\mu }\left(z\right)=\exp \left(-z/2\right)z^{\mu +{\tfrac {1}{2}}}U\left(\mu -\kappa +{\tfrac {1}{2}},1+2\mu ,z\right).}</annotation>
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</math></span><img src="./168e90f1eaf09716fcd53dc4d50d258f33b32c3a.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.171ex; width:52.174ex; height:4.843ex;" alt="{\displaystyle W_{\kappa ,\mu }\left(z\right)=\exp \left(-z/2\right)z^{\mu +{\tfrac {1}{2}}}U\left(\mu -\kappa +{\tfrac {1}{2}},1+2\mu ,z\right).}" loading="lazy"></span></dd></dl>
<p>The Whittaker function <span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle W_{\kappa ,\mu }(z)}">
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<annotation encoding="application/x-tex">{\displaystyle W_{\kappa ,\mu }(z)}</annotation>
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</math></span><img src="./62dbbcfb3ebd6067f413d9390282fa77e8835c40.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:7.719ex; height:3.009ex;" alt="{\displaystyle W_{\kappa ,\mu }(z)}" loading="lazy"></span> is the same as those with opposite values of <span class="texhtml mvar" style="font-style:italic;">μ</span>, in other words considered as a function of <span class="texhtml mvar" style="font-style:italic;">μ</span> at fixed <span class="texhtml mvar" style="font-style:italic;">κ</span> and <span class="texhtml mvar" style="font-style:italic;">z</span> it is <a href="Even_function" class="mw-redirect" title="Even function">even functions</a>. When <span class="texhtml mvar" style="font-style:italic;">κ</span> and <span class="texhtml mvar" style="font-style:italic;">z</span> are real, the functions give real values for real and imaginary values of <span class="texhtml mvar" style="font-style:italic;">μ</span>. These functions of <span class="texhtml mvar" style="font-style:italic;">μ</span> play a role in so-called Kummer spaces.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup>
</p><p>Whittaker functions appear as coefficients of certain representations of the group SL<sub>2</sub>(<b>R</b>), called <a href="Whittaker_model" title="Whittaker model">Whittaker models</a>.
</p>
<div class="mw-heading mw-heading2"><h2 id="References">References</h2></div>
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<ul><li><cite id="CITEREFJacquet1966" class="citation cs2">Jacquet, Hervé (1966), "Une interprétation géométrique et une généralisation P-adique des fonctions de Whittaker en théorie des groupes semi-simples", <i>Comptes Rendus de l'Académie des Sciences, Série A et B</i>, <b>262</b>: <span class="nowrap">A943 –</span> <span class="nowrap">A945</span>, <a href="ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a>&nbsp;<a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/0151-0509">0151-0509</a>, <a href="MR_(identifier)" class="mw-redirect" title="MR (identifier)">MR</a>&nbsp;<a rel="nofollow" class="external text" href="https://mathscinet.ams.org/mathscinet-getitem?mr=0200390">0200390</a></cite></li></ul></li>
<li><cite id="CITEREFJacquet1967" class="citation cs2">Jacquet, Hervé (1967), <a rel="nofollow" class="external text" href="http://www.numdam.org/item?id=BSMF_1967__95__243_0">"Fonctions de Whittaker associées aux groupes de Chevalley"</a>, <i>Bulletin de la Société Mathématique de France</i>, <b>95</b>: <span class="nowrap">243–</span>309, <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.24033%2Fbsmf.1654">10.24033/bsmf.1654</a></span>, <a href="ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a>&nbsp;<a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/0037-9484">0037-9484</a>, <a href="MR_(identifier)" class="mw-redirect" title="MR (identifier)">MR</a>&nbsp;<a rel="nofollow" class="external text" href="https://mathscinet.ams.org/mathscinet-getitem?mr=0271275">0271275</a></cite></li>
<li><cite id="CITEREFRozov2001" class="citation cs2">Rozov, N.Kh. (2001) [1994], <a rel="nofollow" class="external text" href="https://www.encyclopediaofmath.org/index.php?title=Whittaker_equation">"Whittaker equation"</a>, <i><a href="Encyclopedia_of_Mathematics" title="Encyclopedia of Mathematics">Encyclopedia of Mathematics</a></i>, <a href="European_Mathematical_Society" title="European Mathematical Society">EMS Press</a></cite>.</li>
<li><cite id="CITEREFSlater1960" class="citation cs2">Slater, Lucy Joan (1960), <i>Confluent hypergeometric functions</i>, <a href="Cambridge_University_Press" title="Cambridge University Press">Cambridge University Press</a>, <a href="MR_(identifier)" class="mw-redirect" title="MR (identifier)">MR</a>&nbsp;<a rel="nofollow" class="external text" href="https://mathscinet.ams.org/mathscinet-getitem?mr=0107026">0107026</a></cite>.</li>
<li><cite id="CITEREFWhittaker1903" class="citation cs2">Whittaker, Edmund T. (1903), "An expression of certain known functions as generalized hypergeometric functions", <i>Bulletin of the A.M.S.</i>, <b>10</b> (3), Providence, R.I.: <a href="American_Mathematical_Society" title="American Mathematical Society">American Mathematical Society</a>: <span class="nowrap">125–</span>134, <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1090%2FS0002-9904-1903-01077-5">10.1090/S0002-9904-1903-01077-5</a></span></cite></li></ul>
<div class="mw-heading mw-heading2"><h2 id="Further_reading">Further reading</h2></div>
<ul><li><cite id="CITEREFHatamzadeh-VarmazyarMasouri2012" class="citation journal cs1">Hatamzadeh-Varmazyar, Saeed; Masouri, Zahra (2012-11-01). <span class="id-lock-subscription" title="Paid subscription required"><a rel="nofollow" class="external text" href="http://www.sciencedirect.com/science/article/pii/S0955799712001129">"A fast numerical method for analysis of one- and two-dimensional electromagnetic scattering using a set of cardinal functions"</a></span>. <i>Engineering Analysis with Boundary Elements</i>. <b>36</b> (11): <span class="nowrap">1631–</span>1639. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1016%2Fj.enganabound.2012.04.014">10.1016/j.enganabound.2012.04.014</a>. <a href="ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a>&nbsp;<a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/0955-7997">0955-7997</a>.</cite></li>
<li><cite id="CITEREFGerasimovLebedevOblezin2012" class="citation journal cs1">Gerasimov, A. A.; Lebedev, Dmitrii R.; Oblezin, Sergei V. (2012). <a rel="nofollow" class="external text" href="https://iopscience.iop.org/article/10.1070/RM2012v067n01ABEH004776/meta">"New integral representations of Whittaker functions for classical Lie groups"</a>. <i>Russian Mathematical Surveys</i>. <b>67</b> (1): <span class="nowrap">1–</span>92. <a href="ArXiv_(identifier)" class="mw-redirect" title="ArXiv (identifier)">arXiv</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://arxiv.org/abs/0705.2886">0705.2886</a></span>. <a href="Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2012RuMaS..67....1G">2012RuMaS..67....1G</a>. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1070%2FRM2012v067n01ABEH004776">10.1070/RM2012v067n01ABEH004776</a>. <a href="ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a>&nbsp;<a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/0036-0279">0036-0279</a>.</cite></li>
<li><cite id="CITEREFBaudoinO'Connell2011" class="citation journal cs1">Baudoin, Fabrice; O'Connell, Neil (2011). <a rel="nofollow" class="external text" href="http://www.numdam.org/item/AIHPB_2011__47_4_1096_0/">"Exponential functionals of brownian motion and class-one Whittaker functions"</a>. <i>Annales de l'Institut Henri Poincaré, Probabilités et Statistiques</i>. <b>47</b> (4): <span class="nowrap">1096–</span>1120. <a href="ArXiv_(identifier)" class="mw-redirect" title="ArXiv (identifier)">arXiv</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://arxiv.org/abs/0809.2506">0809.2506</a></span>. <a href="Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2011AIHPB..47.1096B">2011AIHPB..47.1096B</a>. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1214%2F10-AIHP401">10.1214/10-AIHP401</a></span>. <a href="S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a>&nbsp;<a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:113388">113388</a>.</cite></li>
<li><cite id="CITEREFMcKee2009" class="citation journal cs1">McKee, Mark (April 2009). <a rel="nofollow" class="external text" href="https://doi.org/10.4153%2FCJM-2009-019-x">"An Infinite Order Whittaker Function"</a>. <i>Canadian Journal of Mathematics</i>. <b>61</b> (2): <span class="nowrap">373–</span>381. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.4153%2FCJM-2009-019-x">10.4153/CJM-2009-019-x</a></span>. <a href="ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a>&nbsp;<a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/0008-414X">0008-414X</a>. <a href="S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a>&nbsp;<a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:55587239">55587239</a>.</cite></li>
<li><cite id="CITEREFMathaiPederzoli1997" class="citation journal cs1">Mathai, A. M.; Pederzoli, Giorgio (1997-03-01). <a rel="nofollow" class="external text" href="https://doi.org/10.1016%2F0024-3795%2895%2900705-9">"Some properties of matrix-variate Laplace transforms and matrix-variate Whittaker functions"</a>. <i>Linear Algebra and Its Applications</i>. <b>253</b> (1): <span class="nowrap">209–</span>226. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1016%2F0024-3795%2895%2900705-9">10.1016/0024-3795(95)00705-9</a></span>. <a href="ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a>&nbsp;<a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/0024-3795">0024-3795</a>.</cite></li>
<li><cite id="CITEREFWhittaker1927" class="citation journal cs1">Whittaker, J. M. (May 1927). <a rel="nofollow" class="external text" href="https://doi.org/10.1017%2FS0013091500007318">"On the Cardinal Function of Interpolation Theory"</a>. <i>Proceedings of the Edinburgh Mathematical Society</i>. <b>1</b> (1): <span class="nowrap">41–</span>46. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1017%2FS0013091500007318">10.1017/S0013091500007318</a></span>. <a href="ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a>&nbsp;<a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1464-3839">1464-3839</a>.</cite></li>
<li><cite id="CITEREFCherednik2009" class="citation journal cs1">Cherednik, Ivan (2009). <a rel="nofollow" class="external text" href="https://ieeexplore.ieee.org/document/8189397">"Whittaker Limits of Difference Spherical Functions"</a>. <i>International Mathematics Research Notices</i>. <b>2009</b> (20): <span class="nowrap">3793–</span>3842. <a href="ArXiv_(identifier)" class="mw-redirect" title="ArXiv (identifier)">arXiv</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://arxiv.org/abs/0807.2155">0807.2155</a></span>. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1093%2Fimrn%2Frnp065">10.1093/imrn/rnp065</a>. <a href="ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a>&nbsp;<a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1687-0247">1687-0247</a>. <a href="S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a>&nbsp;<a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:6253357">6253357</a>.</cite></li>
<li><cite id="CITEREFSlater1954" class="citation journal cs1">Slater, L. J. (October 1954). <span class="id-lock-subscription" title="Paid subscription required"><a rel="nofollow" class="external text" href="https://www.cambridge.org/core/journals/mathematical-proceedings-of-the-cambridge-philosophical-society/article/expansions-of-generalized-whittaker-functions/E011E597828132A26531306D6794C7C3">"Expansions of generalized Whittaker functions"</a></span>. <i><a href="Mathematical_Proceedings_of_the_Cambridge_Philosophical_Society" title="Mathematical Proceedings of the Cambridge Philosophical Society">Mathematical Proceedings of the Cambridge Philosophical Society</a></i>. <b>50</b> (4): <span class="nowrap">628–</span>631. <a href="Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1954PCPS...50..628S">1954PCPS...50..628S</a>. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1017%2FS0305004100029765">10.1017/S0305004100029765</a>. <a href="ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a>&nbsp;<a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1469-8064">1469-8064</a>. <a href="S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a>&nbsp;<a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:122348447">122348447</a>.</cite></li>
<li><cite id="CITEREFEtingof1999" class="citation arxiv cs1">Etingof, Pavel (1999-01-12). "Whittaker functions on quantum groups and q-deformed Toda operators". <a href="ArXiv_(identifier)" class="mw-redirect" title="ArXiv (identifier)">arXiv</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://arxiv.org/abs/math/9901053">math/9901053</a></span>.</cite></li>
<li><cite id="CITEREFMcNamara2011" class="citation journal cs1">McNamara, Peter J. (2011-01-15). <a rel="nofollow" class="external text" href="https://projecteuclid.org/euclid.dmj/1292509116">"Metaplectic Whittaker functions and crystal bases"</a>. <i>Duke Mathematical Journal</i>. <b>156</b> (1): <span class="nowrap">1–</span>31. <a href="ArXiv_(identifier)" class="mw-redirect" title="ArXiv (identifier)">arXiv</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://arxiv.org/abs/0907.2675">0907.2675</a></span>. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1215%2F00127094-2010-064">10.1215/00127094-2010-064</a>. <a href="ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a>&nbsp;<a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/0012-7094">0012-7094</a>. <a href="S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a>&nbsp;<a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:979197">979197</a>.</cite></li>
<li><cite id="CITEREFMathaiPederzoli1998" class="citation journal cs1">Mathai, A. M.; Pederzoli, Giorgio (1998-01-15). <a rel="nofollow" class="external text" href="https://doi.org/10.1016%2FS0024-3795%2897%2900059-1">"A whittaker function of matrix argument"</a>. <i>Linear Algebra and Its Applications</i>. <b>269</b> (1): <span class="nowrap">91–</span>103. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1016%2FS0024-3795%2897%2900059-1">10.1016/S0024-3795(97)00059-1</a></span>. <a href="ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a>&nbsp;<a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/0024-3795">0024-3795</a>.</cite></li>
<li><cite id="CITEREFFrenkelGaitsgoryKazhdanVilonen1998" class="citation journal cs1">Frenkel, E.; Gaitsgory, D.; Kazhdan, D.; Vilonen, K. (1998). <a rel="nofollow" class="external text" href="https://www.ams.org/jams/1998-11-02/S0894-0347-98-00260-4/">"Geometric realization of Whittaker functions and the Langlands conjecture"</a>. <i>Journal of the American Mathematical Society</i>. <b>11</b> (2): <span class="nowrap">451–</span>484. <a href="ArXiv_(identifier)" class="mw-redirect" title="ArXiv (identifier)">arXiv</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://arxiv.org/abs/alg-geom/9703022">alg-geom/9703022</a></span>. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1090%2FS0894-0347-98-00260-4">10.1090/S0894-0347-98-00260-4</a></span>. <a href="ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a>&nbsp;<a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/0894-0347">0894-0347</a>. <a href="S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a>&nbsp;<a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:13221400">13221400</a>.</cite></li></ul></div><!--htdig_noindex--><div><div class="zim-footer">
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