A long-standing claim by critics of the LDS Church is that Joseph Smith plagiarised from other writings to produce the Book of Mormon and other texts; for a good refutation of this charge, see Jeff Lindsay's LDSFAQ page on this issue (as well as his satirical exposé of the parallelomania critics often engage in). Also, see Ted Jones' MA dissertation on the writings of Joseph Smith and Thomas Dick (refuting Fawn Brodie and others).
To compare and contrast Joseph Smith's purported plagiarism with that of another religious leader who was a contemporary of Joseph Smith, see this paper by S. Young on John Thomas (1805-1871) and his (rather obvious) plagiarism from previous authors in the composition of Elpis Israel (1849) and other works:
S. Young, "The Truth: Plagiarism and the Christadelphian founder"
To compare and contrast Joseph Smith's purported plagiarism with that of another religious leader who was a contemporary of Joseph Smith, see this paper by S. Young on John Thomas (1805-1871) and his (rather obvious) plagiarism from previous authors in the composition of Elpis Israel (1849) and other works:
S. Young, "The Truth: Plagiarism and the Christadelphian founder"
