Humphreys, A. C. (1912). Lecture notes on some of the business features of engineering practice (Rev. and enl.). Department of Economics of Engineering, Stevens Institute of Technology.

Humphreys, Alexander Crombie. Lecture Notes on Some of the Business Features of Engineering Practice. Rev. and enl. Hoboken, N.J.: Department of Economics of Engineering, Stevens Institute of Technology, 1912.

Humphreys, Alexander Crombie. Lecture Notes on Some of the Business Features of Engineering Practice. Rev. and enl. Department of Economics of Engineering, Stevens Institute of Technology, 1912.