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Borel morphism

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\begin{document}
\begin{definition}
Let $\grp_B$ and $\grp_B$* be two groupoids whose object spaces are Borel. An \emph{algebraic morphism} from $\grp_B$
to $\grp_B$* is defined as a left action of $\grp_B$ on $\grp_B$* which commutes with the multiplication on $\grp_B$. Such an algebraic morphism between Borel groupoids is said to be a \emph{Borel morphism} if the action of $\grp_B$ on $\grp_B$* is Borel (viz. ref. \cite{MRB2k6})

\end{definition}


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\bibitem{MRB2k6}
M.R. Buneci. 2006.,
\PMlinkexternal{Groupoid C*-Algebras.}{http://www.utgjiu.ro/math/mbuneci/preprint/p0024.pdf},
{\em Surveys in Mathematics and its Applications}, Volume 1: 71--98.

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