Siddiqi's book is excellent. I would also recommend the following:<br /><br />1) "The Soviet Reach for The Moon: The L-1 and L-3 Manned Lunar Programs and the story of the N-1 Moon Rocket" by Nicholas L. Johnson, 1995<br /><br />2) "S.P. Korolev Space Corporation Energia: From first satellite to Energia - Buran and Mir"... originally from Energia and reprints now available through Apogee Books.<br /><br />Number 1 is the best of the bunch, IMHO. It is 52 pages with a great deal of pictures along with a useful bibliography if you are interested in extending your reading. It was published by the now-defunct 'Cosmos Books' although every so often, a copy comes available through a second-hand seller. Libraries, ebay, or Amazon may be useful in tracking one down.<br /><br />Number 2 was originally put out by Energia but more recently Apogee Books has picked it up and is publishing it verbatim (as near as I can tell after a quick flip through it) although in a smaller sized format. It doesn't have much in the way of text regarding N-1/L-3 but it does have a bunch of good photographs.