Three books about the 6th and 9th and the Ross' Texas Brigade are Fighting With Ross' Texas Cavalry Brigade CSA, the Diary of George L. Griscom, Adjutant, 9th TX Cav Rgt; Victor Rose's Fighting With Ross' Texas Brigade, and Newton Asbury Keen's Living and Fighting with the 6th TX Cav ( Which was Ross' first unit), Add to that Petter Cozzen's book on the Battle of Iuka and Corinth. Managed to find a copy of Keen's book, and e-book of Rose's book, and inter library loan from Waco for Griscom's Diary and received Cozzen's book for Christmas(yes, there is a Santa Claus) Still have more to read, so may run across your Brock's yet.