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Lifting Möbius groups: Addendum
J. O. Button
Abstract:
We show that if $\Gamma$ is a group with $H^2(\Gamma; \mathbb Z_2)=0$ then every representation of $\Gamma$ into $\pslc$ lifts to $\slc$, but the converse does not hold.
Selwyn College, Cambridge, CB3 9DQ, U.K. jb128@dpmms.cam.ac.uk http://www.dpmms.cam.ac.uk/site2000/Staff/button01.html