Checkoway, H., Pearce, N., & Crawford-Brown, D. J. (1989). Research methods in occupational epidemiology. Oxford University Press.
Dyfyniad Arddull ChicagoCheckoway, Harvey, Neil Pearce, and Douglas J. Crawford-Brown. Research Methods in Occupational Epidemiology. New York: Oxford University Press, 1989.
Dyfyniad MLACheckoway, Harvey, et al. Research Methods in Occupational Epidemiology. Oxford University Press, 1989.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.