Wałkówski, Andrzej. “The Origin of Office Documents of Soltis, Peter, Racibor Wojcechowicz and Three Representatives of Ancestry Odrowąż for the Cistercian Monastery in Mogiła from the Years 1228–1231”. Piśmiennictwo Zakonne W Dobie Staropolskiej, edited by Magdalena Kuran et al., vol. III, Lodz University Press, 2013, pp. 95-104, https://doi.org/10.18778/7525-996-4.07.