32
Man: Variation in Solar Ultraviolet at Different Latitudes may have Caused
Racial Differentiation in May,” Science, pp. 501-506.
Margo, Robert, and Richard H. Steckel (1983) “Heights of Native Born Northern Whites
during the Antebellum Era.” Journal of Economic History 43: 167-174.
Margo, Robert and Richard Steckel. 1992, “The Nutrition and Health of Slaves and
antebellum Southern whites.” in Without Consent or Contract: Conditions of
Slave Life and the Transition to Freedom, edited by R. W. Fogel and S. L.
Engerman, New York: Norton, 508-521.
McPherson, James., Battle Cry of Freedom. Oxford University Press: Oxford. (1988).
Nesby-O’Dell, Shanna, Kelley Scanlon, Mary Cogswell, Cathleen Gillesie, Bruce Hollis
Anne Looker, Chris Allen, Cindy Doughertly, Elaine Gunter, and Barbara
Bowman. “Hypovitaminosis D Prevalence and Determinants among African-
American and White Woman of Reproductive Age: Third National Health and
Nutrition Examination Survey, 1988-1994.” American Journal Clinical Nutrition
76. 2002. pp. 187-192.
Nicholas, Stephen and Richard Steckel, “Heights and Living Standards of English
Workers During the Early Years of Industrialization.” Journal of Economic
History. 51(4), 1991, pp. 937-957.
Norman, Anthony, “Sunlight, Season, Skin Pigmentation, Vitamin D and 25-
hydroxyvatamin D: Integral Components of the Vitamin D Endocrine System,”
American Journal of Clinical Nutrition, 67. 1998, pp. 1108-1110.
Rosenbloom, Joshua, Looking for Work, Searching for Workers: American Labor