Elsewhere on this website you will find my article about Le Petit Bi, the 16-inch wheel French folding bicycle designed in the 1930s by A J Marcelin of Paris. Riders included the philosopher Jean Paul Sartre and the artist Francis Picabia. Below are some additional pictures to supplement those in the original article.
The first is a press advertisement for the first version of the bike, showing it in ready-to-ride and stowed modes. The advert is undated but probably from about 1939.
The second picture is of the later version of the bike, as patented during the later stages of WW2, which featured a hinged frame. (There is a lower resolution version of this image, which was used in a press advertisement discovered by Bob Cordon Champ, in the main article.)
Lastly, there is a photo (ex-Cycling magazine) of their reviewer Alex Josey testing the bike. He erroneously ascribed the bike to the aviator and intelligence officer Louis Armandias, who merely brought the demonstrator models to London from France on behalf of a friend of his father.