Williams, C. A., & .Heins, R. M. (1981). Risk management and insurance (4th ed.). McGraw-Hill.
Chicago (17e ed.) BronvermeldingWilliams, C. Arthur, en Richard M. .Heins. Risk Management and Insurance. 4th ed. New York: McGraw-Hill, 1981.
MLA (9e ed.) BronvermeldingWilliams, C. Arthur, en Richard M. .Heins. Risk Management and Insurance. 4th ed. McGraw-Hill, 1981.