http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
12.689/257 -- EXCAVATION-OPERATIONS -- Excavation Operations. - Washington:U.S. -- Government Pr.Off.(1963).V,17 S. 8° -- (Occupational hazards to young workers.17.) -- (U.S.Department of Labor.Bureau of Labor -- Standards.Bulletin 257.) -- 1964:2265 d. -- Sz.- -- Arbeitsschutz in gewerblichen Betrieben -- Jugendliche
U.S. Department of Labor. Bureau of Labor Standards. Bulletin 257