Area codes 419 and 567 - Wikipedia
North American Numbering Plan, 978-613-0-09057-9, 6130090579 ,9786130090579
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File:The Bell System technical journal (1922) (14570186909).jpg - Wikimedia Commons
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Original area codes implemented under the North American Numbering Plan with the number of pulses required to dial the area code on a rotary phone. More 'desirable' area codes with a center
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IURC: Establishing New Area Codes
