Joel, A. E. (1976). Electronic switching: Central office system of the world. Institute of Electrical and Electronics Engineers.
Trích dẫn kiểu ChicagoJoel, Amos E. Electronic Switching: Central Office System of the World. New York: Institute of Electrical and Electronics Engineers, 1976.
Trích dẫn MLAJoel, Amos E. Electronic Switching: Central Office System of the World. Institute of Electrical and Electronics Engineers, 1976.
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