The Stone Age Diet: Based on in-depth studies of human ecology and the diet of man by Walter L. Voegtlin. This was self-published back in 1975. Only a couple hundred copies were printed and distributed to friends and relatives. No one knew the book existed until some years later. In no way is he the father of the paleo diet. It is impossible to purchase. Apparently his descendents are planning a reprint, though the book is poorly written and not based upon factual anthropological information that even was available then. We have put up his Functional and Structural Comparison of Man's Digestive Tract with that of a Dog and Sheep. And a PDF can be found here.
While the diet as a whole may not be as varied as your regular diet, it does include enough rich and nutritious foods that it should meet your body’s basic needs. The diet only lasts three days, which means you’ll soon be able to eat a greater variety of foods that will fill in the gaps you’ve missed while dieting. If you were to keep following the diet, repeating the 3-day cycle over and over, you’d run into serious nutritional deficiencies.
Change gradually. If you now eat only one or two servings of fruits or vegetables a day, try to add a serving at lunch and one at dinner. Rather than switching to all whole grains, start by making one or two of your grain servings whole grains. Increasing fruits, vegetables and whole grains gradually can also help prevent bloating or diarrhea that may occur if you aren't used to eating a diet with lots of fiber. You can also try over-the-counter products to help reduce gas from beans and vegetables.