Summum Stereoscopic Apparatus Catalog July 1932
French commercial catalog for Summum high-precision stereoscopic devices (models 6x13, 7x13) and hermetic cases for automatic development. Features product specifications, construction principles, optical components, decentering adjustments, eyepieces, viewfinder options, format details, and comparative stereoscopic photographs demonstrating depth of field effects. Manufacturer: Louis Leullier, Paris.
