Não informado. (1937). Industrial hygiene digest. Industrial Hygiene Foundation of America.
Lua i Stíl Chicago (17ú heag.)Não informado. Industrial Hygiene Digest. Pittsburgh, Pa: Industrial Hygiene Foundation of America, 1937.
Lua MLA (8ú heag.)Não informado. Industrial Hygiene Digest. Industrial Hygiene Foundation of America, 1937.
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