View source for Clémenceau, 1909, The frontier question

Reproduces a letter sent by French Prime Minister Georges Clemenceau to the Prefects of the Departments, advising local authorities to notify the French government of German balloon landings, and to verify that aerial missions have valid scientific purposes. The editor adds:

<blockquote>This letter, although it refers to balloons, of course applies equally to flying machines, and it deserves to be placed on record as the first official acknowledgment of what will ultimately develop into a vast international question, because of the impossibility of patrolling frontiers in the air.</blockquote>

{{Publication
|Original title=The frontier question
|Simple title=The frontier question
|Authors=Georges Clémenceau
|Date=1909-06-01
|Countries=GB
|Languages=en
|Keywords=military; Georges Clémenceau; LTA; airplane; FR; DE; air traffic; département; administration; science; borders; international
|Journal=The Aero
|Related to aircraft=1
|Page count=1
}}
=== Sources ===
* [[Brockett (1921)]], page [https://archive.org/details/bibliographyofa190916broc/page/271 271], entry 21: Clémenceau, M. The frontier question.  Aero, Vol. 1, No. 2 (June 1, 1909), London, p. 29. (B2p0271e21)
* [https://babel.hathitrust.org/cgi/pt?id=uc1.c2564582&view=1up&seq=33&size=125 Scan] at HathiTrust