Não informado. (1909). Telephone engineer and management. Advanstar Communications.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. Telephone Engineer and Management. Chicago, Ill: Advanstar Communications, 1909.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. Telephone Engineer and Management. Advanstar Communications, 1909.
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