This collection of three novels by the creator of Retief features three heroes on interstellar adventures.
Galactic Odyssey (aka Spaceman!) was first serialized in IF magazine (May-July, 1967) and first published in novel form by Berkley in 1967.
"A Trip to the City" (aka "It Could Be Anything") was first published in Amazing, January 1963.
"Hybrid" was first published in The Magazine of F&SF in November 1961.
"Combat Unit" (aka "Dinochrome") was first published in The Magazine of F&SF in November 1960.
"The King of the City" was first published in Galaxy in August 1961.
"Once There Was a Giant" was first published in The Magazine of F&SF in November 1968.
Dinosaur Beach was first published by Scribner's in 1971.