Catalogue of galaxies and of clusters of galaxies / prepared by F. Zwicky with the collaboration of C.T. Kowal. Vol. 6, Covering the Palomar survey fields of the declination zones [plus] 24° [plus] 30°, [plus] 36°, [plus] 42°, [plus] 48°, [plus]
Publisher: Pasedena (Calif.) : California Institute of Technology