LC database, Feb. 4, 2002 (hdg.: Petri, Laurentius, Abp., 1499-1573; usage: Laurentius Petri, archevêque d'Uppsala (1531-1573), Laurentius Petri)
Nordisk familjebok, 1911, online, viewed 2 Oct. 2012 (Laurentius Petri, latinised form of Lars Peterson, the elder; b. 1499 in Örebro (whence the surname Nericius, signifying "from Närke"))