Safety code series
U.S. G.P.O
Illuminating Engineering Society, New York, N.Y., sponsor ; tentative American standard, approved November, 1922, by American Engineering Standards Committee
U.S. G.P.O. 1923 Bulletin / Bureau of Labor Statistics no. 350 , Safety code series
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U.S. G.P.O. 1923 Bulletin / Bureau of Labor Statistics no. 351 , Safety code series
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prepared under sponsorship of Illuminating Engineering Society
G.P.O. 1923 Safety code series , Bulletin / Bureau of Labor Statistics no. 331
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