Brian Hollingsworth & Arthur Cook 1987: , Salamander Books Ltd., London, ISBN 9780517645154. Edmund Keilty; Interuban Press 1979, ISBN 0-916374-38-6 William D. Middleton 1968: , s. 72; Kalmbach Publishing Co, fourth printing 1968; http://www.archive.org/stream/interurbanera00midd/interurbanera00midd_djvu.txt.