Reference

S.J. Greenwood, M.L. Sogin, Denis Lynn (1991): Phylogenetic relationships within the class Oligohymenophorea, Phylum Ciliophora, inferred from the complete small subunit rTNA gene sequences of Colpidium campylum, Glaucoma chattoni, and Opisthonecta henneguyi – J. Mol. Evol. – 33: 163 - 174.