The book "Great Western Steam - Double headed" by Colin L Williams, published in 1975, focuses on the steam locomotives of the Great Western Railway (GWR) and the Western Region of the United Kingdom. This railwayana book is a valuable resource for enthusiasts interested in the history and operations of the GWR, particularly in relation to steam locomotives. With a specific emphasis on double-headed steam trains, the book likely provides detailed information and images that showcase this unique aspect of railway operations on the GWR.