• [Wiki] http://en.wikipedia.org/wiki/Passer_montanus.
• [avibase] https://avibase.bsc-eoc.org/species.jsp?lang=EN&avibaseid=469D6B56AC698B71&sec=lifehistory.
• [Chae1997] Chae, H.-Y. (1997). Variations in fledging body weight and wing length of russet sparrow Passer rutilans in two different habitats. Jap. J. Ornithol., 45:215--223. doi:10.3161/068.039.0209.
• [Kooy2010] Kooijman, S. (2010). Dynamic Energy Budget theory for metabolic organisation. Cambridge Univ. Press, Cambridge.
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