Book on the US Army Cavalry between WWI and II

I am a military history buff and I was interested in this movie because it dealt with the last years of the US Army Cavalry.

Here is a book about US Army Cavalry between WWI and II for those who would like more information on this topic.

The Twilight of the U.S. Cavalry: Life in the Old Army, 1917-1942 (Modern War Studies)

http://www.amazon.com/gp/product/0700609326/ref=olp_product_details?ie=UTF8&me=