APA (7th ed.) Citation

Couper, H., & Henbest, N. (1997). Buracos negros (1ª.). Gradiva.

Chicago Style (17th ed.) Citation

Couper, Heather, and Nigel Henbest. Buracos Negros. 1ª. Gradiva, 1997.

MLA (8th ed.) Citation

Couper, Heather, and Nigel Henbest. Buracos Negros. 1ª. Gradiva, 1997.

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