Many Caswell references in Wells, Merle W. -- "Gold Camps & Silver Cities/Nineteenth Century Mining in Central and Southern Idaho." Idaho Department of Lands, Bureau of Mines & Geology, Moscow, Idaho, 1983.
As well as Helmer, Cheryl. -- "Warren Times/A collection of news about Warren, Idaho." Henington Publishing Company, Wolfe City, TX., 1988. Includes the greater Warren area.
Helmer's book is oversized & bound, maybe 12" x 24".