APA (7th ed.) Citation

K, M., H, L., B, V., & H, M. (2003). Serum retinol levels and the risk of fracture. New England Journal of Medicine, 348(4), 287.

Chicago Style (17th ed.) Citation

K, Michaëlsson, Lithell H, Vessby B, and Melhus H. "Serum Retinol Levels and the Risk of Fracture." New England Journal of Medicine 348, no. 4 (2003): 287.

MLA (9th ed.) Citation

K, Michaëlsson, et al. "Serum Retinol Levels and the Risk of Fracture." New England Journal of Medicine, vol. 348, no. 4, 2003, p. 287.