C. Metz, Matthew A. Vucetich, John W. Smith, Douglas R. Stahler, Daniel O. Peterson, Rolf Map of the Northern Range. <p>Northern Range wolves were monitored from 1997 to 2009.</p> ecology 2011-03-01
    https://plos.figshare.com/articles/figure/_Map_of_the_Northern_Range_/465125
10.1371/journal.pone.0017332.g001