http://solomonspalding.com/docs2/1914Shk1.htm#pg055b
http://lavazone2.com/dbroadhu/OH/evan1832.htm#000043
Thomas Clapp, a deacon in the church where Rigdon preached, confirmed Bentley’s statement:
“Elder Adamson Bentley told me that as he was one day riding with Sidney Rigdon and conversing upon the Bible, Mr. Rigdon told him that another book of equal authority with the bible, as well authenticated and as ancient, which would give an account of the history of the Indian tribes on this continent, with many other things of great importance to the world, would soon be published.”