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Nishi A, Ishida K, Endoh H (junho de 2005). «Reevaluation of the evolutionary position of opalinids based on 18S rDNA, and alpha- and beta-tubulin gene phylogenies». Journal of Molecular Evolution. 60 (6): 695–705. PMID15931497. doi:10.1007/s00239-004-0149-x !CS1 manut: Nomes múltiplos: lista de autores (link)