1. American Petroleum Institute,Annual Statistical Review, 1975, Washington, D.C.
2. Anderson, Lee F., Meredity W. Watts, Jr., and Allen R. Wilcox,Legislative Roll Call Analysis Northwestern University Press, Evanston, 1966.
3. Independent Petroleum Association of America, “Vote Talley on Energy,”Petroleum Independent, Vol. XLV, No. 6 (November, 1975).
4. Jackson, John E., “Statistical Models of Senate Roll Call Voting,”American Political Science Review, Vol. LXV, No. 2 (June, 1971).
5. Silberman, Jonathan I. and Garey C. Durden, “Determining Legislative Preferences on the Minimum Wage: An Economic Approach,”Journal of Political Economy Vol. 84, No. 2 (April, 1976).