Keystone's map of the coal fields of the United States McGraw Hill Published: 1976 Total Pages: Get eBook
Catalog of Books and Reports in the Bureau of Mines Technical Library, Pittsburgh, Pa United States. Bureau of Mines. Technical Library, Pittsburgh Published: 1968 Total Pages: 792 Get eBook
Teachers' Guide for the Use of the "600 Set" of Keystone Stereographs and Lantern Slides for Visual Instruction Douglas Clay Ridgley Published: 1911 Total Pages: 360 Get eBook
