Karen Anderson & Poul Anderson 
The Golden Age of Science Fiction — Volume XV 

The unbelievable, awesomely awesome, FIFTEENTH volume of the Golden Age of Science Fiction!! Featuring: Project Mastodon, by Clifford Simak The Holes Around Mars, by Jerome Bixby Big Ancestor, by F.L. Wallace Jack of No Trades, by Evelyn E. Smith The Piebald Hippogriff, by Karen Anderson Shipwreck in the Sky, by Eando Binder Sentiment, Inc., by Poul Anderson Postmark Ganymede, by Robert Silverberg The Next Logical Step, by Ben Bova Tedric, by E.E. Smith