Permissible Mine Equipment Approved by the Bureau of Mines During 1965-66

A Supplement to Bulletin 543 and Information Circulars 8220 and 8299

by C. M. Mason, David J. Kusler, Edward Eugene Johnson, F. R. Lee, Henry C. Meeves, Herbert S. Kalman, John J. Henn, Thomas M. Nasiatka, H. A. Corre, Harold J. Bennett, P. A. Richardson, Ralph C. Kirby, Richard P. Darnell, Lindsay D. Norman · 1968