- ↑ Some Orthodox Churches use the Julian calendar rather than the Gregorian used in the West. Since 1900, the Julian calendar is 13 days behind the Gregorian calendar, and this difference will remain until 2100. During this period, 22 May in the Julian calendar—the Feast of Saint Jovan Vladimir for those Churches—corresponds to 4 June in the Gregorian calendar.
- ↑ Fine 1991, pp. 193, 202