Логос 2017, p. 174, 175. His name appears in the papal correspondence from 1236, in which it is written about Sibislav, Prince of Usora that he is the son of Stephani bani de Bosna. Логос, Александар А. (2017). Историја Срба I. Београд. ISBN978-86-85117-37-4.{{cite book}}: CS1 maint: location missing publisher (link)