PART 2 - FOUR HIDDEN CHIMNEYS CHAPTER 10: BUILDING-BLOCK REALITY The Great Rewiring

"A 1992 HTTP status-code document already defined Payment Required 402 and described a ChargeTo payment mechanism."

The W3C's archived 1992 HTTP material contains PaymentRequired 402 and describes a payment-related ChargeTo header, establishing how early payment semantics appeared in HTTP's development.

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