Germany, Luftstreitkräfte. A Signed Wartime Photo of Oswald Boelcke

(Luftstreitkräfte Porträt mit Unterschrift). A rare signed wartime photo of First World War Luftstreitkräfte ace and fighter combat theorist Oswald Boelcke, depicted in uniform and wearing a Pour le Mérite, a 1914 Iron Cross II Class ribbon, a 1914 Iron Cross I Class, and a Prussian Pilot’s Badge, with Boelcke’s handwritten signature in blue ink clearly visible across the lower half of the image, the lower right of the obverse bearing a mark of a Berlin-based studio, undated, measuring 86 mm (w) x 136 mm (h), a rare signed Boelcke memento in near extremely fine condition; accompanied by a second portrait of a Luftstreitkräfte pilot, depicted in a flight cap and greatcoat, with a handwritten name of “JOHANN SCHMID” and date of 14 April 1918, the reverse bearing an additional handwritten inscription, measuring 90 mm (w) x 140 mm (h), in near extremely fine condition.