I’ve discovered that the “year” field has disappeared from the entry editor (unless set explicitly in the code) and replaced by “date.” Is there an explanation for this, considering that most .bst styles (say, AMS, i.e., essentially, the styles) use “year” and ignore “date”? In fact, it’s a must field for them. Can this go back to the required fields?
Your library is in biblatex format (and biblatex uses “date” and not “year”) and I guess you are expecting a BibTeX file.
Go to LIbrary -> Library properties, and change the library mode (2nd item). That’s it!
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