Frm the top
First picture - really too many to mention
Second - Polish Gotha IV , 1920
Third - Fokker D.VII, Fokker D.VIII monoplane, Siemens-Schukert Werke(SSW) D.IV, SSW D.III, Aviatik Berg D.I, 1918
Fourth - Oeffag 153 (Albatros D.III variant, made in Austria-Hungary), 1918
Fifth - AEG G.IV bomber and G.IVk armoured attack aircraft, 1918
WWII - From the back - 1941-1942
French Curtiss H-75(P-36), Chinese H-75(P-36)
RAF Curtiss Tomahawk (P-40D), RAF Westland Whirlwind, Soviet Polikarpov I-15bis (Biplane), German Messerschmidt Bf 110D
Finnish P-36, Finnish Brewster Buffalo, US Bell P-39D Airacobra, Japanese Nakajima Ki-27 "Nate", Chinese Polikarpov I-16
German Bf110D, Dutch P-36, Japanese Nakajima Ki-43 "Oscar", RAF Whirlwind
Soviet (ex-RAF) Bell P-400, Soviet I-16, Dutch Buffalo, Soviet I-16
Soviet I-15bis
WWII again (All biplanes) 1940
Chinese I-15bis
Chinese Gloster Gladiator I, Swedish Volunteer Squadron(Finland) Gladiator I
Russian I-15bis, Finnish Gladiator II, Belgian Fiat CR42
Hungarian Cr42, Belgian Gladiator I