June 23 (Eastern Orthodox liturgics) (English Wikipedia)

The Roman Martyrology. Transl. by the Archbishop of Baltimore. Last Edition, According to the Copy Printed at Rome in 1914. Revised Edition, with the Imprimatur of His Eminence Cardinal Gibbons. Baltimore: John Murphy Company, 1916. pp. 182-183.
Rev. Sabine Baring-Gould (M.A.). "S. AGRIPPINA, V.M. (ABOUT A.D. 258.)." In: The Lives of the Saints. Volume the Sixth: June. London: John C. Nimmo, 1897. p. 308.
Rev. Sabine Baring-Gould (M.A.). "S. FELIX, P.M. (A.D. 257.)." In: The Lives of the Saints. Volume the Sixth: June. London: John C. Nimmo, 1897. pp. 307-308.
Rev. Sabine Baring-Gould (M.A.). "S. JOHN, P.M. (A.D. 362.)." In: The Lives of the Saints. Volume the Sixth: June. London: John C. Nimmo, 1897. p. 309.
Very Rev. John O'Hanlon. "ARTICLE I.—ST. MOCHAOI OR MOCHAY, ABBOT AND PATRON OF AND PATRON OF NENDRUM, COUNTY OF DOWN. [FIFTH CENTURY.]." In: Lives of the Irish Saints: With Special Festivals, and the Commemorations of Holy Persons. VOL. VI. Dublin, 1875. pp. 769-779.
Rev. Richard Stanton. A Menology of England and Wales, or, Brief Memorials of the Ancient British and English Saints Arranged According to the Calendar, Together with the Martyrs of the 16th and 17th Centuries. London: Burns & Oates, 1892. pp. 285-287.
Very Rev. John O'Hanlon. "Article VI.—Reputed Festival of St. Hildulph, Bishop of Treves, and of SS. Argobast, Florentius, Fidelis and Adeodatus, Companions." In: Lives of the Irish Saints: With Special Festivals, and the Commemorations of Holy Persons. VOL. VI. Dublin, 1875. p. 780.
Rev. Sabine Baring-Gould (M.A.). "S. JACOB, B. OF TOUL. (8TH CENT.)." In: The Lives of the Saints. Volume the Sixth: June. London: John C. Nimmo, 1897. pp. 309-310.
Rev. Sabine Baring-Gould (M.A.). "S. WALHERE, P.M. (DATE UNCERTAIN.)." In: The Lives of the Saints. Volume the Sixth: June. London: John C. Nimmo, 1897. pp. 318-319.

ecclesia.gr

(in Greek) Συναξαριστής. 23 Ιουνίου. ECCLESIA.GR. (H ΕΚΚΛΗΣΙΑ ΤΗΣ ΕΛΛΑΔΟΣ).

holytrinityorthodox.com

July 6 / June 23. HOLY TRINITY RUSSIAN ORTHODOX CHURCH (A parish of the Patriarchate of Moscow).

impeh.gr

(in Greek) Ακολουθία Αγίων Ενδόξων Νεομαρτύρων. Ecumenical Patriarchate - Holy Metropolis of Petra and Hersonissos. Retrieved: 2 May 2018. 9 pages. (Acolouthia. PDF).

johnsanidopoulos.com

Life and Miracles of Saint Barbaros the Myrrhgusher. Mystagogy Resource Center. May 15, 2011. Retrieved 2 May 2018.

oca.org

Martyr Agrippina of Rome. OCA - Lives of the Saints.
Martyr Eustochius of Ancyra. OCA - Lives of the Saints.
Righteous Artemius of Verkola. OCA - Lives of the Saints.
Meeting of the Vladimir Icon of the Mother of God in memory of the Saving of Moscow from the Invasion of Khan Achmed. OCA - Lives of the Saints.
Icon of the Mother of God “Tenderness” of the Pskov Caves. OCA - Lives of the Saints.
Second Translation of the relics of St Herman the Archbishop of Kazan. OCA - Lives of the Saints.

orthochristian.com

June 23/July 6. Orthodox Calendar (PRAVOSLAVIE.RU).

orthodoxengland.org.uk

June 23. Latin Saints of the Orthodox Patriarchate of Rome.

orthodoxresearchinstitute.org

Dr. Detorakis, Theocharis (University of Crete). "Brief Historical Review of the Holy Archdiocese of Crete." ORTHODOX RESEARCH INSTITUTE. Retrieved: 2 May 2018.

pravenc.ru

(in Russian) АЛЕКСАНДР. Православная Энциклопедия под редакцией Патриарха Московского и всея Руси Кирилла (электронная версия). (Orthodox Encyclopedia - Pravenc.ru).
(in Russian) АЛЕКСИЙ. Православная Энциклопедия под редакцией Патриарха Московского и всея Руси Кирилла (электронная версия). (Orthodox Encyclopedia - Pravenc.ru).
(in Russian) Собор Владимирских святых (23 июня). Православная Энциклопедия под редакцией Патриарха Московского и всея Руси Кирилла (электронная версия). (Orthodox Encyclopedia - Pravenc.ru).

rop.ru

calendar.rop.ru

(in Russian) 23 июня по старому стилю / 6 июля по новому стилю. Русская Православная Церковь - Православный церковный календарь на 2017 год.

saint.gr

(in Greek) 23/06/2018. Ορθόδοξος Συναξαριστής.

synaxarion.gr

Great Synaxaristes: (in Greek) Ἡ Ἁγία Ἀγριππίνα ἡ Μάρτυς. 23 ΙΟΥΝΙΟΥ. ΜΕΓΑΣ ΣΥΝΑΞΑΡΙΣΤΗΣ.
Great Synaxaristes: (in Greek) Οἱ Ἅγιοι Ἀριστοκλῆς, Δημητριανὸς καὶ Ἀθανάσιος οἱ Μάρτυρες ἐν Κύπρῳ ἀθλήσαντες. 23 ΙΟΥΝΙΟΥ. ΜΕΓΑΣ ΣΥΝΑΞΑΡΙΣΤΗΣ.
Great Synaxaristes: (in Greek) Ὁ Ἅγιος Εὐστόχιος ὁ Πρεσβύτερος καὶ οἱ σὺν αὐτῷ. 23 ΙΟΥΝΙΟΥ. ΜΕΓΑΣ ΣΥΝΑΞΑΡΙΣΤΗΣ.
Great Synaxaristes: (in Greek) Ὁ Ὅσιος Ἡσύχιος τῆς Βάτου. 23 ΙΟΥΝΙΟΥ. ΜΕΓΑΣ ΣΥΝΑΞΑΡΙΣΤΗΣ.
Great Synaxaristes: (in Greek) Ὁ Ὅσιος Βάρβαρος ὁ Μυροβλήτης. 23 ΙΟΥΝΙΟΥ. ΜΕΓΑΣ ΣΥΝΑΞΑΡΙΣΤΗΣ.
Great Synaxaristes: (in Greek) Ἡ Ὁσία Ἐθελδρέδα ἡ βασίλισσα. 23 ΙΟΥΝΙΟΥ. ΜΕΓΑΣ ΣΥΝΑΞΑΡΙΣΤΗΣ.
Great Synaxaristes: (in Greek) Ὁ Ὅσιος Νικήτας ἐκ Θηβῶν. 23 ΙΟΥΝΙΟΥ. ΜΕΓΑΣ ΣΥΝΑΞΑΡΙΣΤΗΣ.
Great Synaxaristes: (in Greek) Ὁ Ἅγιος Ἀρτέμιος ἐν Βέρκολᾳ Ρωσίας. 23 ΙΟΥΝΙΟΥ. ΜΕΓΑΣ ΣΥΝΑΞΑΡΙΣΤΗΣ.
Great Synaxaristes: (in Greek) Ὁ Ἅγιος Καλλίνικος ὁ Ἱερομάρτυρας ἐκ Βεροίας. 23 ΙΟΥΝΙΟΥ. ΜΕΓΑΣ ΣΥΝΑΞΑΡΙΣΤΗΣ.
Great Synaxaristes: (in Greek) Οἱ Ἅγιοι Γεράσιμος, Νεόφυτος, Ἰωακείμ, Ἱερόθεος, Ζαχαρίας, Ἰωακείμ, Γεράσιμος, Καλλίνικος, Μελχισεδέκ, Καλλίνικος οἱ Ἱερομάρτυρες καὶ οἱ σὺν αὐτοῖς ἀθλήσαντες κληρικοὶ καὶ λαϊκοὶ ἐν ἔτεσιν 1821 καὶ 1822. 23 ΙΟΥΝΙΟΥ. ΜΕΓΑΣ ΣΥΝΑΞΑΡΙΣΤΗΣ.
Great Synaxaristes: (in Greek) Οἱ Ἅγιοι ἅπαντες Μάρτυρες ἐν Βλαδιμὶρ τῆς Ρωσίας. 23 ΙΟΥΝΙΟΥ. ΜΕΓΑΣ ΣΥΝΑΞΑΡΙΣΤΗΣ.
Great Synaxaristes: (in Greek) Σύναξις Ὑπεραγίας Θεοτόκου τοῦ Βλαδιμήρου ἐν Κιέβῳ. 23 ΙΟΥΝΙΟΥ. ΜΕΓΑΣ ΣΥΝΑΞΑΡΙΣΤΗΣ.
Great Synaxaristes: (in Greek) Σύναξις Ὑπεραγίας Θεοτόκου τῆς Τρυφερῆς. 23 ΙΟΥΝΙΟΥ. ΜΕΓΑΣ ΣΥΝΑΞΑΡΙΣΤΗΣ.

wikipedia.org

ru.wikipedia.org

See: (in Russian) Дионисий Полоцкий. Википедии. (Russian Wikipedia).
See: (in Russian) Митрофан (Краснопольский). Википедии. (Russian Wikipedia).
See: (in Russian) Максим (Жижиленко). Википедии. (Russian Wikipedia).
See: (in Russian) Концевич, Иван Михайлович. Википедии. (Russian Wikipedia).