Research on the elk lungworm Dictyocaulus sp was carried out in the spring (early June) and summer (mid-July) of 1972. Project Number 156.
Bergstrom, Robert C.
"Parasites of Ungulates in the Jackson Hole Area,"
Jackson Hole Research Station Annual Report: Vol. 1972
, Article 23.
Available at: http://repository.uwyo.edu/jhrs_reports/vol1972/iss1/23