MLA style dictates that multiple authors (3 or more) be cited, in text, using "et al." Yet I can't seem to get Zotero to do this - instead, all the authors are listed out. What am I missing?
MLA requires et al for more than three authors (not 3 or more) - i.e. up to three authors are listed. The style should do that correctly. If it doesn't, re-install it from the repository.
Also, see if the problem also occurs in a new document.
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Also, see if the problem also occurs in a new document.