I am using BibTeX and Natbib (author-year) for citing references in my document. Whenever there are three authors or more for a given paper, the citation will be "First author et al. (year)". This is the way I would like it to be in general.
However, when the paper is cited for the first time in a document, I would like all the names to appear, ie "First author, second author, and third author (year)". I know I can achieve this manually by \cite*. But is there also a way to have this done automatically on the first occurrence?