Funded by the National Science Foundation PEET program (Partnerships for Enhancing Expertise in Taxonomy)
Khan, M. A. 1957b. Sphaerularia ungulacauda sp. nov. (Nematoda: Allantonematidae) from the Douglas fir beetle, Dendroctonus pseudotsugae Hopk., with key to Spaerularia species (emended). Canadian Journal of Zoology 35(16):635-639, 5 figs.