Between 1076 and 1080, while he was at Zaragoza, Sisnando is said to have finally convinced Paterno to come west and take up the see of Coimbra. But the document of 1 March 1088 on which this claim is made is not trustworthy and the notion that the king sent Sisnando to Zaragoza for just such a purpose as recruiting a bishop is false. A Paternus was bishop of Coimbra as early as 20 November 1078. He is last mentioned as bishop on 1 March 1088 and never appears as a confirmant of a royal document.