3 ms·

Two more examples of exchanges that were kept secret: https://en.wikipedia.org/wiki/Anchor_telephone_exchange https://en.wikipedia.org/wiki/Anchor_telephone_ex

by biofox 1y ago

Two more examples of exchanges that were kept secret: https://en.wikipedia.org/wiki/Anchor_telephone_exchange https://en.wikipedia.org/wiki/Anchor_telephone_exchange https://en.wikipedia.org/wiki/Guardian_telephone_exchange https://en.wikipedia.org/wiki/Guardian_telephone_exchange