ESSEN ELECTRONICS. (1987). SN-PC PC-XT USER MANNUAL. ESSEN ELECTRONICS.
Chicago Style aipamenaESSEN ELECTRONICS. SN-PC PC-XT USER MANNUAL. BOMBAY: ESSEN ELECTRONICS, 1987.
MLA aipamenaESSEN ELECTRONICS. SN-PC PC-XT USER MANNUAL. ESSEN ELECTRONICS, 1987.
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