APA (7th ed.) Citation

Guarner, F., & Malagelada, J. (2003). Gut flora in health and disease. Lancet, 361(9356), 512. https://doi.org/10.1016/S0140-6736(03)12489-0

Chicago Style (17th ed.) Citation

Guarner, Francisco, and Juan-R Malagelada. "Gut Flora in Health and Disease." Lancet 361, no. 9356 (2003): 512. https://doi.org/10.1016/S0140-6736(03)12489-0.

MLA (9th ed.) Citation

Guarner, Francisco, and Juan-R Malagelada. "Gut Flora in Health and Disease." Lancet, vol. 361, no. 9356, 2003, p. 512, https://doi.org/10.1016/S0140-6736(03)12489-0.