• [Wiki] http://en.wikipedia.org/wiki/Progne_subis.
• [AnAge] https://genomics.senescence.info/species/entry.php?species=Progne_subis.
• [avibase] https://avibase.bsc-eoc.org/species.jsp?lang=EN&avibaseid=ACB9D1C6AB7F3371&sec=lifehistory.
• [AlleNice1952] Allen, R. W. and Nice, M. M. (1952). A study of the breeding biology of the purple martin (Progne subis). 47(3):606--665.
• [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.