Quién?

From Author Wars - https://authorwars.com/publications/quien-555078.html

Overview:

Title: Quién?
Author: Algis Budrys
Year: 1961
Publisher: Cenit
Pages: 203
Binding: Paperback
Type: Novel
Title Reference: Quién?
Notes: Translated by José María Cañas Cover art is signed but not recognizable; cover is a virtual copy of Who? by Robert Engle