In July and August of 1969, 33 Microtus pennsylvanicus, 20 M. montanus, 21 Clethrionomys gapperi, 3 Zapus princeps, and 19 Sorex sp. were trapped in two areas in Jackson Hole, Wyoming by Tim W. Clark. Several milligrams of hair from the mid-dorsal region of each animal was collected for trace element analysis at the National Reactor Testing Station in Idaho by the author. Project Number 170.
Huckabee, John W.
"Trace Elements in Small Mammal Hair,"
Jackson Hole Research Station Annual Report: Vol. 1969
, Article 12.
Available at: https://repository.uwyo.edu/jhrs_reports/vol1969/iss1/12