Subject: Question for the list From: "John Olsen" Date: Thu, 22 Feb 2007 22:26:17 -0300 Consider a three dimensional lens space S3/\Z_k with an action of Z_2 + Z_2. If k is odd this space is a Z_2 cohomology sphere and hence the action is not free. If k is even is it still true that the action cannot be free? Any references are much appreciated! Thank you, John Olsen