Burroughs doesn't call it a diet. It's a fast, because you don't consume solid foods. There are many fasts in the Fasting Forum. I like the green juices the best. Burroughs' fast has the special purpose of mobilizing and eliminating toxins with minimum nutritional interference: Just enough to get the job done. Each ingredient has a purpose in the lemonade.
Do you have a copy of the book? If you don't, you can find it posted in the CZ's books section, or a link to the same books section in my blog. The most important pages are pp 14 - 16, if I recall correctly, but the entire books is quite interesting.
(added later): I see AilsaRose gave you the links. Thanks!