Sealy, Spencer G. “Evening Grosbeaks Feeding on Pupae of the Forest Tent Caterpillar in the Dune- Ridge Forest, Delta Marsh, Manitoba, Spring 1976”. Blue Jay 76, no. 1 (March 15, 2018): 24–25. Accessed May 15, 2022. https://bluejayjournal.ca/index.php/bluejay/article/view/19.