Langsdorf, A. S. (1940). Principles of direct-current machines (5th ed.). McGraw-Hill book company, inc..
芝加哥风格引文Langsdorf, Alexander Suss. Principles of Direct-current Machines. 5th ed. New York and London: McGraw-Hill book company, inc., 1940.
MLA引文Langsdorf, Alexander Suss. Principles of Direct-current Machines. 5th ed. McGraw-Hill book company, inc., 1940.
警告：这些引文格式不一定是100％准确.