Surely it would be possible to set "N/A" automatically for several of the secondary sources, where the date of the pub is past the date of the verification source?
Instead of automatically setting such records, we could just disallow such (much like how we skip bibliographic warnings in a number of cases; e.g. ISBNs magazines and pubs before 1966, etc.). Such things are not really useful/valuable when we already know there is no possibility for verification anyway.
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Instead of automatically setting such records, we could just disallow such (much like how we skip bibliographic warnings in a number of cases; e.g. ISBNs magazines and pubs before 1966, etc.). Such things are not really useful/valuable when we already know there is no possibility for verification anyway.