^D.C. Blood; J.A. Henderson; O.M. Radostits (1979). Veterinary Medicine (5th ed.). London: Baillière Tindall. pp. 611–612.
ISBN0-7020-0718-8.
^H. Graham Purchase and L.N. Payne, Leukosis/sarcoma Group, in Diseases of poultry, ed. by M.S. Hofstad, Iowa State University Press, Ames, Iowa, USA
ISBN0-8138-0430-2, p. 360-405