I'm not very familiar with TEMPER, but as far as I know it is the only
format under consideration that can handle non-Gregorian dates (EDTF
does not, correct?). This has been a problem for us for a while, and
though TEMPER (or any other format) doesn't automatically solve problems
of interoperability with other calendars that may arise, having a way to
encode the data would certainly be a start.
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