http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
Operating regulations to govern coal-­mining methods and the safety and welfare of miners on leased lands on the public domain, under the act of Feb. 25, 1920 (41 Stat. 437), and amendments thereto, second edition
1 online resource (46 pages), digital, PDF file
Electronic reproduction. [Bethesda, Md.] : ProQuest, 2017 digital, PDF file. ProQuest U.S. Executive Branch Documents Mode of access: World Wide Web via ProQuest website.