\ifx\undefined\bysame
\newcommand{\bysame}{\leavevmode\hbox to3em{\hrulefill}\,}
\fi
\begin{thebibliography}{10}

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\bibitem{Dri83Ham}
V.~G. Drinfeld, {\em Hamiltonian structures on {L}ie groups, {L}ie bialgebras
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\bibitem{DriSok84Alg}
V.~G. Drinfeld and V.~V. Sokolov, {\em Lie algebras and equations of
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\bibitem{FeiFre91Sem}
B.~L. Feigin and Edward Frenkel, {\em Semi-infinite {W}eil complex and the
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\bibitem{GelDick78}
I.~M. Gelfand and L.~A. Dickey, {\em A family of {H}amiltonian structures
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\bibitem{KheZakhGD}
Boris Khesin and Ilya Zakharevich, {\em The {G}elfand--{D}ickey structure and
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\bibitem{LuWei90Poi}
Jiang-Hua Lu and Alan Weinstein, {\em Poisson {L}ie groups, dressing
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\bibitem{Rad91Non}
A.~O. Radul, {\em Nontrivial central extensions of {L}ie algebras of
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\bibitem{Sem83Wha}
M.~A. Semenov-Tyan-Shanskii, {\em What a classical $r$-matrix is}, Akademiya
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\bibitem{Sem85Dre}
\bysame, {\em Dressing transformations and {P}oisson group actions}, Kyoto
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\end{thebibliography}