• [Wiki] http://en.wikipedia.org/wiki/Lanius_collaris.
• [avibase] https://avibase.bsc-eoc.org/species.jsp?lang=EN&avibaseid=B936AAF3C05775B7&sec=lifehistory.
• [Coop1971] Cooper, J. (1971). Post-nestling development in the fiscal shrike. Ostrich, 42(3):175–178. doi:10.1080/00306525.1971.9634402.
• [Kooy2010] Kooijman, S. (2010). Dynamic Energy Budget theory for metabolic organisation. Cambridge Univ. Press, Cambridge.
• [PrinPres1991] Prinzinger, R., A.Preßmar, and Schleucher, E. (1991). Body temperature in birds. Comp. Biochem. Physiol., 99A(4):499--506. doi:10.1016/0300-9629(91)90122-S.