Read W.F. (1991).Two relatively young impact craters near Waupun, Wisconsin // Meteoritics, Vol. 26, p. 387.
Monika Kumlehn de Mamani & Ingrid Grambow IMPAKTNAMEN: Namen der [Meteorite; Impakte/Krater; Boliden/Fireballs; Tektite] im Sonnensystem.(2010)

Рельеф Google.