Question: how were the lord of the rings books released?
Answer: In the United States, Houghton Mifflin published The Fellowship of the Ring on 21 October 1954, The Two Towers on 21 April 1955, and The Return of the King on 5 January 1956. ... Because the three-volume binding was so widely distributed, the work is often referred to as the Lord of the Rings "trilogy".