Reproductive patterns and attempts at reciprocal crossing of Rhabditis elegans maupas, 1900, and Rhabditis briggsae Dougherty and nigon, 1949 (Nematoda: Rhabditidae). Victor Nigon and Ellsworth C. Dougherty, JEZ-A Ecological and Integrative Physiology, Volume 112, Issue 3, December 1949, Pages 485–503, doi:10.1002/jez.1401120307
