The best-known publication produced by the Tanners is "Mormonism: Shadow or Reality?," originally published in 1963 as "Mormonism: A Study of Mormon History and Doctrine", and reprinted five times since. Dean M. Helland of Oral Roberts University describes it as "the heavyweight of all books on Mormonism". The Tanners question the character and integrity of the witnesses to the Book of Mormon; they discuss the different accounts that Joseph Smith gave of the First Vision. Their book includes copies of original LDS documents.