Subject: question Date: Tue, 3 Aug 2004 10:51:32 +0900 From: "???" To: "Don Davis" Dear Don Davis I would like to know the literature(books or paper) somewhere with relation to the following well-known fact : Let p: X \to Y and q: Y \to Z be covering maps. We know that if q^{-1}(z) is finite for each z in Z, then the composition map of the maps p and q is also a covering map and further, if q^{-1}(z) is not finite the statement aboe fails. Sincerely yours, Sang-Eon Han