Bergwall was convicted in January 1996 of murdering a Dutch couple, Marinus and Janni Stegehuis, who were stabbed in Appojaure in 1984.

BBC: Sweden retrial for 'serial killer' Sture Bergwall

He gives due credit to another key source, Marinus of Tyre, whose map was the first to include both China and the Antarctic.

WSJ: Lost in Our Maps: A History of Cartographic Catastrophes