Ludman, A., & Coch, N. K. (1982). Physical geology. McGraw-Hill.
芝加哥风格引文Ludman, Allan, 与 Nicholas K. Coch. Physical Geology. New York: McGraw-Hill, 1982.
MLA引文Ludman, Allan, 与 Nicholas K. Coch. Physical Geology. McGraw-Hill, 1982.
警告：这些引文格式不一定是100％准确.