13.
R. T. Sawyer. : North American Freshwater Leeches, exclusive of the Piscicolidae, with a Key to all Species. Illinois Biological Mongraphs 46, University, of Illinois Press, Urbana, Chicago and New York, 1972, 154 S., 19 Abb., 18 Karten, 315 Lit., $ 8,50
机译:R. T. Sawyer. : North American Freshwater Leeches, exclusive of the Piscicolidae, with a Key to all Species. Illinois Biological Mongraphs 46, University, of Illinois Press, Urbana, Chicago and New York, 1972, 154 S., 19 Abb., 18 Karten, 315 Lit., $ 8,50