April 30 (Eastern Orthodox liturgics) (English Wikipedia)

Rev. Sabine Baring-Gould (M.A.). "S. Maximus, M. (About A.D. 250.)" In: The Lives of the Saints. Volume the Fourth: April. London: John C. Nimmo, 1897. p. 369.
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. 121-122.
Rev. Sabine Baring-Gould (M.A.). "S. Donatus, B. of Evrœa. (About A.D. 387.)" In: The Lives of the Saints. Volume the Fourth: April. London: John C. Nimmo, 1897. p. 373.
Rev. Sabine Baring-Gould (M.A.). "SS. Marian, James, and Comp., MM. (About A.D. 259.)" In: The Lives of the Saints. Volume the Fourth: April. London: John C. Nimmo, 1897. pp. 371-373.
Rev. Sabine Baring-Gould (M.A.). "S. Eutropius, B.M. (3rd cent.)" In: The Lives of the Saints. Volume the Fourth: April. London: John C. Nimmo, 1897. pp. 370-371.
Rev. Sabine Baring-Gould (M.A.). "S. Erkonwold, B. of London. (A.D. 693.)" In: The Lives of the Saints. Volume the Fourth: April. London: John C. Nimmo, 1897. p. 375.
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. 186-189.
Very Rev. John O'Hanlon. "Article I.—St. Forannan, Bishop, and Abbot of Wasor, or Waulsor, Belgium. [Tenth Century.]." In: Lives of the Irish Saints: With Special Festivals, and the Commemorations of Holy Persons. VOL. IV. Dublin, 1875. pp. 552-566.
Rev. Sabine Baring-Gould (M.A.). "S. Forannan, Ab. of Waulsor. (A.D. 982.)" In: The Lives of the Saints. Volume the Fourth: April. London: John C. Nimmo, 1897. pp. 376-377.

holytrinityorthodox.com

May 13 / April 30. Holy Trinity Russian Orthodox Church (A parish of the Patriarchate of Moscow).

oca.org

ocafs.oca.org

Apostle James the Brother of St John the Theologian. OCA - Feasts and Saints.
Icon of the Mother of God "of the Passion". OCA - Feasts and Saints.
Uncovering of the relics of St Basil the Bishop of Amasea. OCA - Feasts and Saints.
Uncovering of the relics of St Nikita the Bishop of Novgorod. OCA - Feasts and Saints.
New Martyr Argyra. OCA - Feasts and Saints.

orthochristian.com

April 30/May 13. Orthodox Calendar (Pravoslavie.ru)

orthodoxengland.org.uk

April 30. Latin Saints of the Orthodox Patriarchate of Rome.

saintpatrickdc.org

April 30 Archived 2011-04-08 at the Wayback Machine. St. Patrick Catholic Church - Saint of the Day.

synaxarion.gr

Great Synaxaristes: (in Greek) Ὁ Ἅγιος Ἰάκωβος ὁ Ἀπόστολος. Μέγας Συναξαριστής.
Great Synaxaristes: (in Greek) Ὁ Ἅγιος Μάξιμος ὁ Μάρτυρας. Μέγας Συναξαριστής.
Great Synaxaristes: (in Greek) Ὁ Ἅγιος Ἀφροδίσιος ὁ Ἱερομάρτυρας καὶ οἱ σὺν αὐτῷ τριάντα Μάρτυρες. Μέγας Συναξαριστής.
Great Synaxaristes: (in Greek) Ὁ Ἅγιος Δονάτος Ἐπίσκοπος Εὐροίας. Μέγας Συναξαριστής.
Great Synaxaristes: (in Greek) Ὁ Ὅσιος Κλήμης ὁ Ὁμολογητής ὁ Ὑμνογράφος. Μέγας Συναξαριστής.
Great Synaxaristes: (in Greek) Ὁ Ἅγιος Λαυρέντιος ὁ Ἱερομάρτυρας καὶ οἱ σὺν αὐτῷ μαρτυρήσαντες. Μέγας Συναξαριστής.
Great Synaxaristes: (in Greek) Ὁ Ἅγιος Ἐρκονγουάλδος Ἐπίσκοπος Λονδίνου. Μέγας Συναξαριστής.
Great Synaxaristes: (in Greek) Οἱ Ἅγιοι Ἰσίδωρος, Ἠλίας καὶ Παῦλος οἱ Μάρτυρες. Μέγας Συναξαριστής.
Great Synaxaristes: (in Greek) Ὁ Ἅγιος Σίμων Μητροπολίτης Μόσχας. Μέγας Συναξαριστής.
Great Synaxaristes: (in Greek) Ὁ Ἅγιος Ἰγνάτιος Ἐπίσκοπος Σταυρουπόλεως. Μέγας Συναξαριστής.
Great Synaxaristes: (in Greek) Εὕρεσις Τιμίων Λειψάνων Ἁγίου Βασιλέως τοῦ Ἱερομάρτυρος. Μέγας Συναξαριστής.
Great Synaxaristes: (in Greek) Ἀνακομιδὴ Τιμίων Λειψάνων Ἁγίου Νικήτα Ἀρχιεπισκόπου Νόβγκοροντ. Μέγας Συναξαριστής.
Great Synaxaristes: (in Greek) Ἀνακομιδὴ Τιμίων Λειψάνων Ἁγίας Ἀργυρῆς τῆς Νεομάρτυρος. Μέγας Συναξαριστής.

ukrainian-orthodoxy.org

Dr. Alexander Roman. April Archived 2017-12-05 at the Wayback Machine. Calendar of Ukrainian Orthodox Saints (Ukrainian Orthodoxy - Українське Православ'я).

web.archive.org

April 30 Archived 2011-04-08 at the Wayback Machine. St. Patrick Catholic Church - Saint of the Day.
Dr. Alexander Roman. April Archived 2017-12-05 at the Wayback Machine. Calendar of Ukrainian Orthodox Saints (Ukrainian Orthodoxy - Українське Православ'я).