Pyle, R. M. (1974). Watching Washington butterflies: An interpretive guide to the State's 134 species, including most of the butterflies of Oregon, Idaho, and British Columbia. Seattle Audubon Society.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Pyle, Robert Michael. Watching Washington Butterflies: An Interpretive Guide to the State's 134 Species, Including Most of the Butterflies of Oregon, Idaho, and British Columbia. [Seattle]: Seattle Audubon Society, 1974.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Pyle, Robert Michael. Watching Washington Butterflies: An Interpretive Guide to the State's 134 Species, Including Most of the Butterflies of Oregon, Idaho, and British Columbia. Seattle Audubon Society, 1974.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.