Hesham,
I'm not sure if the projects illustrated in "Les avions à aile gouttière de Willard Custer" are real or not. They certainly look plausible (Willard Custer was convinced that most airframes could be advantageously adapted to his Channel Wing concept). The cover shot just looks like the usual PM artist's impression scaled-up from the CCW-1.
Attached are a few projects that can definitely be attributed to Custer.
BTW, the 1947 project with military stars-and-bars and similar tailplane to the Piper PA-23 'Twin Stinson' which suggests a Baumann connection. Baumann built CCW prototypes and, of course, the CCW-5 fuselage was based on Baumann's own B290 Brigadier prototype.
http://patentroom.com/custer-airplane-design-1955
http://patentroom.com/channel-wing-airplane-1956
http://patentroom.com/custer-channel-wing-airplane-design-1956
http://www.airspacemag.com/history-of-flight/lunch-with-willard.html?c=y&page=1
See: http://www.custerchannelwing.com/05_dreams.html for a Custer twin-seat STOL project (bottom of the page). Also on that page, the later but Custer-related 1985-86) P20 Raider and P50 Devastator projects by the Product Development Group (1985-86).
http://www.custerchannelwing.com/05_dreams_p20.html
http://www.custerchannelwing.com/05_dreams_p50.html