Where Do You Get Your Ideas? Don't Ask Jack London.
"...when [Sinclair] Lewis was starting out, he picked up some money by suggesting story ideas to [Jack] London."
-- Herbert Mitgang, "Sinclair Lewis Recalled in Grolier Club Display," NYT, 17 Feb. 1985
More here regarding the London-Lewis relationship; also see this article on Lewis by Gore Vidal.
About the photos: Jack London (top); Sinclair Lewis. Library of Congress, Prints and Photographs Division