found: 91-198626: Axelrod, H.R. Swordtails and platies, c1991:p. 47 (Xiphophorus helleri Heckel, 1848 sy: X. helleri helleri Del Campo, X. guentheri Jordan and Everman, X. helleri guentheri Hubbs, X. jalapae Meek, X. strigatus Regan, X. helleri strigatus De Buen, X. brevis Regan, X. helleri brevis Hubbs and Gordon, X. rachovi Regan)
found: Comp. aquarium encyc. of tropical freshwater fish:p. 310 (Xiphophorus ... The Helleri group which includes S. clemenciae, the Yellow Swordtail, X. helleri alvarezi, X. helleriguentheri, X. helleri helleri and X. helleri strigatus; Xiphophorus helleri helleri, Eng. name: Swordtail)
found: Sterba aquarium encyc.(Swordtail (Xiphophorus helleri) see Xiphophorus (Xiphophorus Heckel Swordtail) Helleri-group (X. clemenciae, X. helleri with sub-species))
found: Coffey encyc. aquarium fish(Xiphophorus helleri Swordtail)