APA

National Institutes of Health (U.S.), . (1973). Interested in environmental health?: [Operation MEDIHC would like to assist you]. [Washington, D.C: .

Chicago

National Institutes of Health (U.S.), . 1973. Interested in environmental health?: [Operation MEDIHC would like to assist you]. [Washington, D.C: .

Harvard

National Institutes of Health (U.S.), . (1973). Interested in environmental health?: [Operation MEDIHC would like to assist you]. [Washington, D.C: .

MLA

National Institutes of Health (U.S.), . Interested in environmental health?: [Operation MEDIHC would like to assist you]. [Washington, D.C: . 1973.