Humorous drawing by Grandjouan from "L'Assiette au Beurre" depicting a city skyline full of boxy biplanes in flight. The caption reads:
"--Doit-on prendre sa droite ou sa gauche ?... Son dessus ou son dessous?..."
["Do we have to keep right or left? Over or under?..."]
"Les Aéroplanes," issue No. 398 of the French satirical periodical "L'Assiette au Beurre," 14 November 1908, page 531.