Polski: RWD-2 Edwarda Więckowskiego podczas próby startu w zawodach Challenge w 1930, 5-7 sierpnia 1930
Polski: Tytuł: 3-ci Krajowy Konkurs Awionetek : 24.IX-6.X 1930 : program konkursu, przebieg i wyniki, regulamin, wyniki 1-go i 2-go K.K.A.Adres wydawniczy: [S.l. : s.n.], 1930 (Warszawa : Fr. Orzechowski)Gatun More
Archduke Anton of Austria in the Challenge International de Tourisme 1930, in Warsaw
Čeština: Junkers A 50, Waldemar Roeder, Challenge 1930 (Letec, 20.10.1930) Public domain photograph of experimental aircraft, prototype, aviation design and development, no copyright restrictions image - Picr More
Čeština: Letoun PWS-8 na soutěži Challenge de Tourisme International 1930
Čeština: Walter Venus a Breda Ba.15-P - vítěz Challenge 1930
The aircraft before the en:Challenge 1930 contest, in Zeppelin hangar at Berlin-Staaken. From the top: SP-ADD - PWS-52 (Poland, pilot Franciszek Rutkowski, not completed) OO-AKY - St. Hubert G1 (Belgium, in t More
The aircraft Caudron C.193 (F-AJSH, pilot Francois Arrachart) and PWS-51 (SP-ADC, pilot Józef Lewoniewski) before en:Challenge 1930 contest (cropped photo Chalenge1930.jpg)
Public domain photograph of pre-war Polish aircraft, Second Polish Republic aviation, free to use, no copyright restrictions image - Picryl description