This American Stamp: Employ the Handicapped

I recently purchased a binder of vintage postage and this page was especially striking. I'd seen the "Employ the Handicapped" stamp before, but never knew the story behind it. This collector carefully pasted in the accompanying article from August 28, 1960. "The stamp," it reads "will picture a man confined to a wheel chair, capably operating a drill press." The stamp was designed by Carl Bobertz, a New York artist. Does anyone know about the original photograph that inspired this design? Or what other work Bobertz has done? All I can find is various comic book covers.

The issuance coincided with the Eighth World Congress of the International Society for the Welfare of Cripples, which was sponsored by the Committee on the Employment of the Physically Handicapped which "promot[ed] employment of physically handicapped workers."