BPP document row of altogether 4 volumes, kpl.1: Maaßen, Wolfgang: The history of the examination nature in the German philately (1860-1945), 2: Van Loo, Wilhelm: The philatelic expertising nature of the post-war period (1945-1958), 3: Penning, Dr. Hans Karl/Oechsner, Dr. Helmut: 50 years bundle of philatelic inspectors (1958-2008), 4: Fisherman, Peter: The philatelic expertising nature in SBZ and DDR (1945-1990), new in OVP (shrink-wrapped)