D..Fothergill, H., Z., J., F., E., L.(1939).Immunity Principles And Application in Medicine And Public Health (5th edition).New York:The MacMillan Company.
Gaya MLA
D..Fothergill, H., Z., J., F., E., L..Immunity Principles And Application in Medicine And Public Health.5th editionNew York:The MacMillan Company,1939.Lawas.