i'm sorry I did not see this message, and your post has languished so long unanswered. The Soil and Health library (online) is a truly priceless resource; full of good works on NH and water fasting. The fellow who hosts it is doing a genuinely noble service. . . (If anyone is able, and inspired, it is good to donate an amount to him to help maintain the site.) I prefer the older literature, since it seems less tainted by a kind of pop tendancy toward recreating the wheel, and almost patenting it.
Through the titles/substance there, you will be led to other works. Best wishes
one thought: the essene gospel of peace (for one) has inspired many people toward the natural hygiene lifestyle, as it were. Interesting, what it proposes in terms of enemas--a thing that there is always discussion about, for and against, when it comes to water fasting. I can say, for myself, in Water Fasts of 29 and 21 days, I never felt compelled to do an enema, and the body released waste on three occasions, on its own, but I can see both sides of the isssue.