Silverberg, Robert (ed.). Worlds of Maybe: Seven Stories of Science Fiction
Summary: Reprints of Poul Anderson's "Delenda Est", Isaac Asimov's "Living Space", Miriam Allen deFord's "Slips Take Over", Philip José Farmer's "Sail On, Sail On", Murray Leinster's "Sidewise in Time", and Larry Niven's "All the Myriad Ways". Also includes one non-allohistorical work by Miriam Allen deFord.
Published: Thomas Nelson 1970 (084076104XBUY); and Dell 1974.