ACE DOUBLE: MONSTERS IN ORBIT / THE WORLD BETWEEN AND OTHER STORIES

Ace pb, 1965. Cover by Jack Gaughan.

Cover by Jack Gaughan - again.

THE HAWKS OF ARCTURUS

DAW pb, 1974. Cover by (Frank) Kelly Freas.

THE PRITCHER MASS

DAW pb, 1973. Cover by (Frank) Kelly Freas.