I've been summoned to provide some references and sources with regards to ketogenic dieting and fasting (and why you would do it!)
Primarily, Drs. Domenic D'Agostino, Rhonda Patrick, Thomas Seyfried, and Valter Longo have a lot of papers examining ketosis for a variety of reasons. Jason Fung has recently come out as a voice of fasting/intermittent fasting, which goes hand in hand with ketosis (as when you're burning your own body fat, you're in a 100% fat burning 'diet'- as ketotic as they come.)
For those who dislike journal articles (or who aren't behind the paywall), Tim Ferriss has done at least two podcasts (The Tim Ferriss Show) with Domenic D'Agostino which go over the whys and hows with a more entertaining story behind it. His podcast with Dr. Peter Attia also goes into this in some detail. Tim's book Tools of the Titans also goes a little more into detail regarding fasting and protocols, but that's a very tiny part of a very large book. I believe several people have interviewed Mark Sisson as well, who is more of a fitness personality rather than a doctor or scientist, but I can appreciate how he tends to evaluate data before making his recommendations.
Dr. Peter Attia also discusses ketogenic diets, the whys and the hows, as well as some excellent breakdowns on the science of ketosis and fasting, and discusses it on the Tim Ferriss Show podcasts and others.
For those who care, my primary weight loss driver was the "4 hour body" by Tim Ferriss. Stupid name, excellent book. His Slow-Carb/Cyclical Ketogenic Diet kept me sane over a long period of weight loss (21 months so far) but the tools recommended in it (DEXA scanning, circumference measurements, before and after pics, etc.) were insanely useful. He also lists some references and materials that were useful.
A good book that has a ton of citations while still being an easy read is "Why We Get Fat (and what to do about it)" by Gary Taubes.