I have found a wonderful book that details the histories of the 22nd, 31st, 34th Cavalries, and 15th Texas Infantry as they fought in Indian Territory and Arkansas in 1862 and then moved to Louisiana in 63. It is called Polignac's Texas Brigade by Alwyn Barr, a professor at Texas Tech. Copyright-1998. Its history begins before Polignac took command of these regiments, and is documented throughout. I found this book through Amazon.com. Another book that is about the Indian Territory wars in general that mentions occasionally the 31st is called Civil War in the Indian Territory by Steve Cottrell. This book is not footnoted like Barr's book, and seems to be written with a sense of dramatic flair, but still a good source of information. I bought this book at the Confederate Museum in Atoka, Oklahoma.