APA (7th ed.) Citation

Allen, N., Morris, J., Ngwenyama, R., & Key, T. (2004). A case--control study of selenium in nails and prostate cancer risk in British men.

Chicago Style (17th ed.) Citation

Allen, N., J. Morris, R. Ngwenyama, and T. Key. A Case--control Study of Selenium in Nails and Prostate Cancer Risk in British Men. 2004.

MLA (9th ed.) Citation

Allen, N., et al. A Case--control Study of Selenium in Nails and Prostate Cancer Risk in British Men. 2004.