It is not unlikely, since it it evidently hapened in the same book, where NZS published wrong cup winners for some seasons. If it happened for cup, why not for league? Those information appeared in books from early nineties, that were mostly made by Stare, 80 years Olimpija, 70 years NZS and "Slovenski nogomet 1992". The information was gathered very fast in those years for varios nationalist and other interests and ther main intence was not to publish verified material, but to publish things about slovenian football, which was something new after the independence. I guarantee that noone has checked those information 10 times and I allready mentioned you before some information used by Stare, that was evidently false (Grafičar, Unior ets.). I really don't understand why you trust to that "faker" Stare so much?