File:North American Numbering Plan NPA map BTM 1947.png

Summary
Original map of 1947 of numbering plan areas in the United States and Canada and their codes. Adapted and corrected for printing error from Bell Telephone Magazine 1947.

Bell Telephone Magazine, v26 p180 (1947), Mabbs R.I. Nation-wide Operator Toll Dialing-the Coming Way

Derived from Bell Telephone Magazine on Wikimedia Commons.