Commercial traffio of Frenoh aerial navigation companies. Number of flights. … Passengers (paying).. 1600 1300 800 400 0 Freight, idooo sc-cco CD aooooS ^10000 Fig. 1; (Taken from "Premier Congres'In- ternational de la Navigation Aerienne", Vol.1, p. 133)
NASA Technical Reports Server (NTRS)
Internet Archive · NASA Technical Reports · Public domain (US government work). Free to use for anything.
![An illustration from ERIC ED542087: [Biennial Survey of Education, 1926-1928. Bulletin, 1930, No. 16. Chapter I - Chapter XX] (1930)](https://img.insideoutlibrary.com/img/200/ia-ERIC_ED542087-443-0.webp)
