American Transit Association, Purdue University. School of Civil Engineering, & National Research Council (U.S.). Highway Research Board. (1973). Public transportation research needs: Proceedings of a conference, Purdue University, November 4-5, 1971. [Highway Research Board] National Research Council.

American Transit Association, Purdue University. School of Civil Engineering, and National Research Council (U.S.). Highway Research Board. Public Transportation Research Needs: Proceedings of a Conference, Purdue University, November 4-5, 1971. Washington, D.C: [Highway Research Board] National Research Council, 1973.

American Transit Association, et al. Public Transportation Research Needs: Proceedings of a Conference, Purdue University, November 4-5, 1971. [Highway Research Board] National Research Council, 1973.