Aronowitz RA. 2001. When do symptoms become a disease? Annals of Internal Medicine 134(9 Pt 2):803-808.
Hill AB. 1965. The Environment and disease: Association or causation? Proceedings of the Royal Society of Medicine 58(10):295-300.
IOM (Institute of Medicine). 2000. Gulf War and Health, Volume 1. Depleted Uranium, Sarin, Pyridostigmine Bromide, Vaccines. Washington, DC: National Academy Press.
Monson R. 1990. Occupational Epidemiology. 2nd ed. Boca Raton, FL: CRC Press, Inc.
Muthen B. 1984. A general structural equation model with dichotomous, ordered, categorical, and continuous latent variable indicators. Psychometrika 49(1):115-132.
Pearl J. 2000. Causality: Models, Reasoning and Inference. Cambridge, UK: Cambridge University Press.
Phillips CV, Goodman KJ. 2004. The missed lessons of Sir Austin Bradford Hill. Epidemiologic Perspectives and Innovations 1(1):3.
Robins E, Guze SB. 1970. Establishment of diagnostic validity in psychiatric illness: Its application to schizophrenia. American Journal of Psychiatry 126(7):983-987.
Taub E, Cuevas JL, Cook EW 3rd, Crowell M, Whitehead WE. 1995. Irritable bowel syndrome defined by factor analysis. Gender and race comparisons. Digestive Diseases and Sciences 40(12):2647-2655.