• [Wiki] http://en.wikipedia.org/wiki/Apeltes_quadracus.
• [fishbase] https://www.fishbase.se/summary/Apeltes-quadracus.html.
• [ADW] https://animaldiversity.org/accounts/Apeltes_quadracus/.
• [CraiFitz1982] Craig, D. and FitzGerald, G. J. (1982). Reproductive tactics of four sympatric sticklebacks (Gasterosteidae). Ehv. Biol. Fish., 7(4):369--375.
• [Kooy2010] Kooijman, S. (2010). Dynamic Energy Budget theory for metabolic organisation. Cambridge Univ. Press, Cambridge.
• [Schw1965] Schwarz, F. J. (1965). Age, growth, and egg complement of the stickleback Apeltes quadracus at Solomons, Maryland. Chesapeake Sci., 6(2):116--118.