Why does the north-south gradient of incidence of multiple sclerosis seem to have disappeared on the northern hemisphere?

MLA

Koch-Henriksen, Nils, and Per Soelberg Sorensen. “Why Does the North-South Gradient of Incidence of Multiple Sclerosis Seem to Have Disappeared on the Northern Hemisphere?” Journal of the Neurological Sciences, vol. 311, no. 1–2, Dec. 2011, pp. 58–63. EBSCOhost, https://doi.org/10.1016/j.jns.2011.09.003.

APA

Koch-Henriksen, N., & Sorensen, P. S. (2011). Why does the north-south gradient of incidence of multiple sclerosis seem to have disappeared on the northern hemisphere? Journal of the Neurological Sciences, 311(1–2), 58–63. https://doi.org/10.1016/j.jns.2011.09.003

Chicago

Koch-Henriksen, Nils, and Per Soelberg Sorensen. 2011. “Why Does the North-South Gradient of Incidence of Multiple Sclerosis Seem to Have Disappeared on the Northern Hemisphere?” Journal of the Neurological Sciences 311 (1–2): 58–63. doi:10.1016/j.jns.2011.09.003.