Foreword by Vivian Fuchs. Introd. by Carroll Lane Fenton. Editorial consultants (English ed.): Norman Harris...[et al.] ; [translated by R. Bradshaw and Mary M. Owen]Prometheus Press1961
by Lucien Rudaux and G. de Vaucouleurs ; with an introd. by F.L. Whipple ; [translated by Michael Guest and John B. Sidgwick ; and rev. by Z. Kopal]Prometheus Press1959