The pterylography of certain American goat-suckers and owlsDOI: info:10.5479/si.00963801.17-1018.551v. 17No. 1018551–572, 11 figs.
Clark, Hubert Lyman. 1895. "The pterylography of certain American goat-suckers and owls." Proceedings of the United States National Museum, 17, (1018) 551–572, 11 figs.. https://doi.org/10.5479/si.00963801.17-1018.551.