A manual of the Infusoria, including a description of all known flagellate, ciliate,
and tentaculiferous protozoa, british and foreign, and an account of the organization
and the affinities of the sponges / by W. Saville Kent, 1881-1882
Internet, http://catalogue.bl.uk, 2006-05-18
Internet, http://members.trump.net.au, 2006-05-18