[en] [Gutenberg 18448] • Transactions of the American Society of Civil Engineers, vol. LXX, Dec. 1910 / Federal Investigations of Mine Accidents, Structural Materials and Fuels. Paper No. 1171 Createspace Independent Publishing Platform
[en] [Gutenberg 18448] • Transactions of the American Society of Civil Engineers, vol. LXX, Dec. 1910 / Federal Investigations of Mine Accidents, Structural Materials and Fuels. Paper No. 1171 Createspace Independent Publishing Platform