[1] RFC 1357 - A Format for E-mailing Bibliographic Records, 2/1/2021, 1:05:26 AM, 3/13/2021, 9:57:25 AM https://tools.ietf.org/html/rfc1357
[2] RFC 1807 - A Format for Bibliographic Records, 1/24/2021, 1:06:15 PM, 3/13/2021, 9:57:33 AM https://tools.ietf.org/html/rfc1807
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