International Seminar on Approval and Gathering Plans in Large and Medium Size Academic Libraries, 3rd., West Palm Beach, Fla., 1971, Spyers-Duran, P., & Gore, D. (1972). Economics of approval plans: Proceedings. Greenwood Press.
Chicago-referens (17:e uppl.)International Seminar on Approval and Gathering Plans in Large and Medium Size Academic Libraries, 3rd., West Palm Beach, Fla., 1971, Peter Spyers-Duran, och Daniel Gore. Economics of Approval Plans: Proceedings. Westport, Conn: Greenwood Press, 1972.
MLA-referens (9:e uppl.)International Seminar on Approval and Gathering Plans in Large and Medium Size Academic Libraries, 3rd., West Palm Beach, Fla., 1971, et al. Economics of Approval Plans: Proceedings. Greenwood Press, 1972.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.