O. M.  Amin, Heckmann, R. A., Mesa, R., and Mesa, E., ?Description and host relationships of cystacanths of Polymorphus spindlatus (Acanthocephala: Polymorphidae) from their paratenic fish hosts in Peru?, Journal of the Helminthological Society of WashingtonJ. HELMINTHOL. SOC. WASH., vol. 62, no. 2, pp. 249 - 253, 1995.