APA (7th ed.) Citation

Harrison, J., & Worfolk, T. (1999). A field guide to the birds of Sri Lanka. Oxford University Press.

Chicago Style (17th ed.) Citation

Harrison, John, and Tim Worfolk. A Field Guide to the Birds of Sri Lanka. Oxford: Oxford University Press, 1999.

MLA (9th ed.) Citation

Harrison, John, and Tim Worfolk. A Field Guide to the Birds of Sri Lanka. Oxford University Press, 1999.

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