APA (7th ed.) Citation

Neill, W., & Hepburn, D. (1976). Butterflies afield in the Pacific Northwest. Pacific Search Books.

Chicago Style (17th ed.) Citation

Neill, William, and Doug Hepburn. Butterflies Afield in the Pacific Northwest. Seattle: Pacific Search Books, 1976.

MLA (8th ed.) Citation

Neill, William, and Doug Hepburn. Butterflies Afield in the Pacific Northwest. Pacific Search Books, 1976.

Warning: These citations may not always be 100% accurate.