Index of average labor cost (including social insurance contributions) per ton of saleble coal [graph comparing European countries in 1925, 1927, 1929, and 1931]
name: label: Collection Creator
content: Missionary Catechists of Divine Providence.
label: Collection Creator
content: Massachusetts Institute of Technology (MIT) Civil Engineering Department
label: Collection Creator
content: Underwood and Underwood
setName: label: See more items in
content: Division of Work and Industry Lantern Slide Collection
label: See more items in
content: Division of Work and Industry Lantern Slide Collection / Series 2: Extractive Industries / 2.1.6: Coal -- International
unitdate: label: Date
content: 1931
container: label: Container
content: Box 83, Item 26
dataSource: label: Archival Repository
content: Archives Center, National Museum of American History
objectType: label: Type
content: Archival materials
label: Type
content: Photographs