A later historical source that explicitly links the idea of Cain to Bigfoot.
Lee D. Bell, South Weber: The Autobiography of One Utah Community (Salt Lake City: K/P Printing, 1990), 513-520
There are Mormons who believe that when the Lord said Cain would be a "fugitive and vagabond in the earth" that He was condemning Cain to wader the earth forever, even to our present era. And there are just as many who believe Bigfoot to the Cain of old.