There is no single authority accepted by all Mormon fundamentalists; viewpoints and practices of individual groups vary. Fundamentalists have formed numerous small sects, often within cohesive and isolated communities in the Western United States, Western Canada, and northern Mexico. At times, sources have claimed there are as many as 60,000 Mormon fundamentalists in the United States, with fewer than half of them living in polygamous households. However, others have suggested that there may be as few as 20,000 Mormon fundamentalists with only 8,000 to 15,000 practicing polygamy. Founders of mutually rival Mormon fundamentalist denominations include Lorin C. Woolley, John Y. Barlow, Joseph W. Musser, Leroy S. Johnson, Rulon C. Allred, Elden Kingston, and Joel LeBaron. The largest Mormon fundamentalist groups are the Fundamentalist Church of Jesus Christ of Latter-Day Saints (FLDS Church) and the Apostolic United Brethren (AUB).