only display all authors, of multi-author works, the first time a citation is used with biblatex - TeX - LaTeX Stack Exchange
Bibliography management with natbib - Overleaf, Online LaTeX Editor
BibTeX doesn't abbreviate to “et al.”
bibliographies - "et al." for 3 or more authors, not 4 or more, authors in a citation call-out with "aea" bibliography style - TeX - LaTeX Stack Exchange
bibtex - Bibliography with author names as last, first - TeX - LaTeX Stack Exchange
Bibliography management with bibtex - Overleaf, Online LaTeX Editor