TransliterationMarkhay E., Bavitskiy I., Zhdanov I. i dr. Avtomaticheskie telefonnye stantsii. Chast 1. Osnovy tekhniki i skhemy ATS. Chast 2. Proektirovanie i eksploatatsiya (ekspluatatsiya) ATS
In EnglishMarkhai E., Bavitsky I., Zhdanov I. et al. Automatic telephone exchanges. Part 1. Fundamentals of technology and PBX circuits. Part 2. Design and exploitation (operation) of PBX In Russian (ask us if in doubt).
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