Oyeyele, S.O. and M.P. Zalucki 1990. Parsons, J.A. 1965. A digitalis-like toxin in the monarch butterfly, Danaus plexippus. Mimicry in butterflies of North America. Roeske, C.N., Seiber, Brower, L.P. and Moffit, C.M. 1976.
Milkweed cardenolides and their comparative processing by monarch butterflies.
Rothschild, M., J. Von Euw, T. Reichstein, D. Smith and J. Pierre. Turner, J. 1984. Van Hook, T. and M.P. Zalucki. Oviposition by Danaus plexippus on Asclepias viridis in northern Florida.