Cosmic engineers: an interplanetary novel

Cosmic Engineers is a science fiction novel by author Clifford D. Simak. It was published in 1950 by Gnome Press in an edition of 6,000 copies, of which 1,000 were bound in paperback for an armed forces edition. The novel was originally serialized in the magazine Astounding in 1939.

Plot
The novel concerns a group of earthmen and a girl, who is awakened from suspended animation, being contacted by aliens with whom they join to prevent the collision of one universe with another.