https://kpfa.org/area941/episode/george-r-r-martin-1991-before-game-of-thrones/
[Note: The following interview is made available through the Internet Archive. The precise date, beyond April 1990, is unknown.]
http://web.archive.org/web/19990503011306/http://www.eidolon.net/old_site/issue_02/02_gmart.htm