[3] 関連: BinHex
[4] RFC 4450: Getting Rid of the Cruft: Report from an Experiment in Identifying and Reclassifying Obsolete Standards Documents, 12/2/2023, 8:22:42 AM, 12/2/2023, 8:29:49 AM https://www.rfc-editor.org/rfc/rfc4450.html#appendix-A
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