Reader's Digest, Vol. 47, #279, July 1945, pp.57-59 (& Feb. 1941, pp.39-43)
Joseph Nathan Kane did a radio show and wrote a book called "Famous First Facts". It was widely popular. For one radio show, he invited Gustave Whitehead's son, Charles, to tell the world about his father's 1901 flight. Kane did further research and became convinced Whitehead had performed history's first powered, sustained, controlled, heaver-than-air, manned flight. He put Whitehead's achievement in his book of "Firsts" and wrote an article about him for Liberty Magazine. That article was then condensed into a shorter article which appeared in Reader's Digest in July, 1945. Here's an excerpt from the text:
"In 1940, (Joseph Nathan) Kane went on the air with [the radio show] 'Famous Firsts'...
"It was during one of these programs that Kane presented Charles Whitehead of
Bridgeport, Conn., as "the son of Gustave Whitehead, the first man to fly a
heavier-than-air machine – two years, four months and three days previous
to the Wright flight at Kitty Hawk. " This was such a sensational claim that it
cost Kane several hundred dollars to convince skeptics. At his own expense he
mailed out thousands of photostatted newspaper clippings describing in detail a
half-mile motor-controlled flight made by Gustave Whitehead, a Bavarian, on
August 14, 1901. These were supplemented with copies of 11 affidavits signed by
eyewitnesses…"