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Kuruppath, Sanjana; Bisana, Swathi; Sharp, Julie A; Lefevre, Christophe; Kumar, Satish; Nicholas, Kevin R (2012년 8월 11일). “Monotremes and marsupials: Comparative models to better understand the function of milk”. 《Journal of Biosciences》 37 (4): 581–588. doi:10.1007/s12038-012-9247-x. Developmental stages of echidna: (A) Echidna eggs; (B) Echidna puggle hatching from egg...
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“Short-beaked Echidna”. Department of Primary Industries, Parks, Water, and Environment. 2013년 4월 13일에 확인함.
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〈echidna〉. 《Online Etymology Dictionary》. 2014년 11월 23일에 확인함.
Dunbar, R.I.M. “The Social Brain Hypothesis”(PDF). 《University of Colorado at Boulder, Department of Psychology and Neuroscience》. 12 April 2016에 원본 문서(PDF)에서 보존된 문서. 4 January 2014에 확인함.