"Christianity: the One, the Many: What Christianity Might Have Been and Could Still Become, Volume 1". Book by John F. Nash (p. 11), February 14, 2008.
"Answers to Correspondents". Essay by Mark Twain, first published in The Californian (June 17, 1865), reprinted in Mark Twain's book "The Celebrated Jumping Frog of Calaveras County, and Other Sketches", 1867.