April 28 (Eastern Orthodox liturgics)

Apr. 27 - Eastern Orthodox Church calendar - Apr. 29

All fixed commemorations below celebrated on May 11 by Orthodox Churches on the Old Calendar.

For April 28th, Orthodox Churches on the Old Calendar commemorate the Saints listed on April 15.

St. Aphrodisius.

St. Adalbero, Bishop of Augsburg.

St. Cyril of Turov.

The Order of St. Cyril of Turov, 2nd degree.

Greek Sources

Russian Sources

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Wikipedia