Kessler, C. (1993). International Scientific Cooperation, Consolidated report of activities, 1987 - 90. s.n.
芝加哥风格引文Kessler, C. International Scientific Cooperation, Consolidated Report of Activities, 1987 - 90. s.l: s.n, 1993.
MLA引文Kessler, C. International Scientific Cooperation, Consolidated Report of Activities, 1987 - 90. s.n, 1993.
警告：这些引文格式不一定是100％准确.