TY - RPRT TI - Molecular techniques to distinguish morphologically similar Hydrilla verticillata , Egeria densa , Elodea nuttallii , and Elodea canadensis AU - Nancy B. Rybicki AU - Julie D. Kirshtein AU - Mary A. Voytek PY - 2013 UR - https://pubs.usgs.gov/publication/70042848 ID - 70042848 ER -