The International Classification of Diseases: 9th revision, Clinical Modification: ICD-9-CM. 6th ed. Washington (DC): Health Care Financing Administration; 1996.
Medical Subject Headings. Bethesda (MD): National Library of Medicine; 1997.
Cote, Roger A., editor. Systemized Nomenclature of Human and Veterinary Medicine: SNOMED International, Version 3.1. Northfield, (IL): College of American Pathologists; Shaumburg, (IL): American Veterinary Medical Association; 1995.
Physicians' Current Procedural Terminology: CPT. 4th ed. Chicago (IL): American Medical Association; 1989.
Logical Observations Identifiers, Names and Codes. LOINC. verion 1.0f. Indianapolis (IN): the Regenstrief Institute; 1996.