Marcus Bach reports the Spaulding theory in an article for Fate magazine.
"The Paranormal Basis of Mormonism," Fate 22 no.2 (February, 1969): 93
Some insist that the Book of Mormon was plagiarized. They point out that a Presbyterian minister, Solomon Spaulding, wrote a story similar to certain accounts in the Book of Mormon. The Spaulding manuscript then is supposed to have fallen into the hands of a Baptist named Sidney Rigdon, who in turn gave it to Joseph Smith.