North American Tunneling Conference Indianapolis, Ind., ebrary, Inc, & Fowler, M. (2012). North American Tunneling: 2012 proceedings. Society for Mining, Metallurgy and Exploration.
Chicago-referens (17:e uppl.)North American Tunneling Conference Indianapolis, Ind., Inc ebrary, och Matthew Fowler. North American Tunneling: 2012 Proceedings. Englewood, Colo.: Society for Mining, Metallurgy and Exploration, 2012.
MLA-referens (9:e uppl.)North American Tunneling Conference Indianapolis, Ind., et al. North American Tunneling: 2012 Proceedings. Society for Mining, Metallurgy and Exploration, 2012.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.