\begin{thebibliography}{51}
\expandafter\ifx\csname natexlab\endcsname\relax\def\natexlab#1{#1}\fi
\providecommand{\enquote}[1]{``#1''}
\expandafter\ifx\csname url\endcsname\relax
  \def\url#1{\texttt{#1}}\fi
\expandafter\ifx\csname urlprefix\endcsname\relax\def\urlprefix{URL }\fi
\providecommand{\eprint}[2][]{\url{#2}}

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J.~A. Minahan, and K.~Zarembo, \emph{JHEP} \textbf{03}, 013 (2003),
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For the current situation see, {``Integrability in String and Gauge Theory''},
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A.~Losev, N.~Nekrasov, and S.~L. Shatashvili, \emph{Nucl. Phys.} \textbf{B534},
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R.~J. Baxter, \emph{Annals Phys.} \textbf{70}, 193--228 (1972{\natexlab{a}})..

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R.~J. Baxter, \emph{Ann. Phys.} \textbf{76}, 25--47 (1973{\natexlab{b}}).

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R.~J. Baxter, \emph{Ann. Phys.} \textbf{76}, 48--71 (1973{\natexlab{c}}).

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E.~Frenkel, and N.~Reshetikhin  (1998), \eprint{math/9810055}.

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I.~Krichever, O.~Lipan, P.~Wiegmann, and A.~Zabrodin, \emph{Commun. Math.
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R.~J. Baxter, \emph{Exactly Solved Models in Statistical Mechanics}, London
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F.~Cachazo, M.~R. Douglas, N.~Seiberg, and E.~Witten, \emph{JHEP} \textbf{12},
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M.~Bershadsky, A.~Johansen, V.~Sadov, and C.~Vafa, \emph{Nucl. Phys.}
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\bibitem[Nekrasov(2003)]{Nekrasov:2003af}
N.~A. Nekrasov  (2003), \eprint{hep-th/0306211}.

\bibitem[Nekrasov and Okounkov(2003)]{Nekrasov:2003rj}
N.~Nekrasov, and A.~Okounkov  (2003), \eprint{hep-th/0306238}.

\end{thebibliography}
