Neumann (Paul) - 'Volksbucher der Techrik Luftchiffe? circa 1913, German text, colour plate of the 'Schwaben' over the Rhine, original boards; Heichen (Walter) - 'Mit Zeppelin und Flugzeug', 1915, German text, with engravings, four colour plates, and cover original cloth and boards; and Von Schiller (Hans) - 'Im Zeppelin Uber der Schweiz'