Lack of HIV infection and condom use in licensed prostitutes.
D000163:Acquired Immunodeficiency Syndrome / Q000453:epidemiology*; D000293:Adolescent; D000328:Adult; D003275:Contraceptive Devices, Male; D005260:Female; D005860:Germany, West; D006801:Humans; D008875:Middle Aged; D011477:Sex Work / Q000331:legislation & jurisprudence*