Barnes, C. H. London: Putnam, 1964. Barnes, C. H. (second ed.) London: Putnam, 1970. Bruce, J. M. (Windsock Datafile No.44). Berkhamsted, Herts, UK: Albatros, 1994. . Shores, Christopher and Rolfe, Mark. Oxford, UK: Osprey, 2001. .