[Bethesda, Md.] : U.S. Dept. of Health, Education, and Welfare, Public Health Service, National Institutes of Health : for sale by the Supt. of Docs., U.S. Govt. Print. Off, 1975
Columbus, Ohio : ERIC Clearinghouse on Vocational and Technical Education, the Center for Vocational and Technical Education, the Ohio State University, 1971