Rowell 2000, p. 707. Rowell, S. C. (2000). "Baltic Europe". In Michael Jones (ed.). The New Cambridge Medieval History c.1300–c.1415. Vol. VI. Cambridge University Press. ISBN0-521-36290-3.
Historians disagree on exact dating: Maciej Stryjkowski provided 1320/21, Aleksandr Ivanovich Rogov argued for 1322, C. S. Rowell for 1323, Feliks Shabuldo for 1324, Romas Batūra [lt] for 1325.[1]
