Burkholder, J. L., & Stephens, R. (1939). Hard rock tunneling. Civil Engineering (08857024), 9, 213.
Chicago Style (17th ed.) CitationBurkholder, J. L., and R. Stephens. "Hard Rock Tunneling." Civil Engineering (08857024) 9 (1939): 213.
MLA (9th ed.) CitationBurkholder, J. L., and R. Stephens. "Hard Rock Tunneling." Civil Engineering (08857024), vol. 9, 1939, p. 213.
Warning: These citations may not always be 100% accurate.