This is the current (11th) edition of Robert's Rules of Order, Newly Revised, the standard reference book on American parliamentary meeting procedure, and the official manual adopted by WSFS to run their meetings, as supplemented by the Standing Rules and the WSFS Constitution. It came out several years ago, but I had put off buying a copy, relying upon my copy of the 10th edition when necessary. However, as I'm presiding this year, and inasmuch as there are some changes between the 10th and 11th editions, I figured I'd better get up to date.
RONR 11, as the book is abbreviated, is 669 pages of main text not counting the index, a 50-page introduction on the history and development of parliamentary law, and a 48-page procedural supplement. I'm now in the process of re-reading the whole thing cover-to-cover, which I have not done in some years.