巣穴
↑ Dubiel, Russel; Blodgett, Robert H; Bown, Thomas M (May 1987). “Lungfish Burrows in the Upper Triassic Chinle and Dolores Formations , Colorado Plateau”. Journal of Sedimentary Petrology 57: 512–521.
↑ Varricchio, David J.; Martin, Anthony J.; and Katsura, Yoshihiro (2007). “First trace and body fossil evidence of a burrowing, denning dinosaur”. Proceedings of the Royal Society B: Biological Sciences 274 (1616): 1361–1368. doi:10.1098/rspb.2006.0443. PMC 2176205. PMID 17374596. http://journals.royalsociety.org/content/uj1k12wh01587821/fulltext.pdf 2007年3月22日閲覧。.
↑ C. Michael Hogan, (2008) Magellanic penguin, Globaltwitcher.com, ed. Nicklas Stromberg