Brands, S. J. (compiler). (1989-2005). Systema Naturae 2000. Amsterdam, The Netherlands (2006 version). Originally available online at http://sn2000.taxonomy.nl/; for current information, refer http://taxonomicon.taxonomy.nl/ProjectDescription.aspx .

basis of record

Flannery, T. F.; Rich, T. H.; Vickers-Rich, P.; Ziegler, T.; Veatch, E. G.; Helgen, K. M. (2022). A review of monotreme (Monotremata) evolution. <em>Alcheringa.</em> 46(1): 3-20.

current name source

Flannery, T. F.; Rich, T. H.; Vickers-Rich, P.; Ziegler, T.; Veatch, E. G.; Helgen, K. M. (2022). A review of monotreme (Monotremata) evolution. <em>Alcheringa.</em> 46(1): 3-20.

taxonomy source

McKenna, M. C.; Bell, S. K. (1997). Classification of Mammals Above the Species Level. Columbia University Press, New York, 631 pp.

name verified source

Systema Naturae 2000 (2006 version)

extant flag source