All right, this is kind of bits and pieces but we can consider this one solved:
Yes, this is the cross country vehicle designed by Emile Petit, as Allan L found. And there are these two pictures of it, whatever Chris Draper says.
Yes, the make is Dommartin. I don't understand how none of you came to that conclusion when Dommartin was quoted by D-type and SeaLion, but there is no sense in going on forever. But, as usual in case of multiple answers, I can't make up my mind about who gets a point, besides Allan.
EDIT: having re-read all the answers, the second point should go to SeaLion who saw that the racecar picture I had added was in fact the Dommartin.