The notation Old Style or (OS) is sometimes used to indicate a date in the Julian Calendar (which is used by churches on the "Old Calendar"). The notation New Style or (NS), indicates a date in the Revised Julian calendar (which is used by churches on the "New Calendar").
"At Gaza, in Palestine, in the time of the emperor Arcadius, St. Porphyry, bishop, who overthrew the idol Marnas and its temple, and after many sufferings, went to rest in the Lord."[13]Name days celebrated today include:
"At Bologna, the bishop St. Faustinian, whose preaching strengthened and multiplied the faithful of that Church, which had been much afflicted during the persecution of Diocletian."[13]
Rev. Sabine Baring-Gould (M.A.). "S. Porphyrius, B. of Gaza (A.D. 421.)." In: The Lives of the Saints. Volume the Second: February. London: John C. Nimmo, 1897. p.434-441.
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.17-18.
Rev. Sabine Baring-Gould (M.A.). "S. DIONYSIUS, B. OF AUGSBURG, M. (A.D. 303.)." In: The Lives of the Saints. Volume the Second: February. London: John C. Nimmo, 1897. p.432-433.
The Autonomous Orthodox Metropolia of Western Europe and the Americas. St. Hilarion Calendar of Saints for the year of our Lord 2004. St. Hilarion Press (Austin, TX). pp.17-18.
February 26. Latin Saints of the Orthodox Patriarchate of Rome.
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.17-18.
(in Greek) Συναξαριστής. 26 Φεβρουαρίου. Ecclesia.gr. (H Εκκλησια τησ Ελλαδοσ).
Russian Sources
(in Russian)11 марта (26 февраля). Православная Энциклопедия под редакцией Патриарха Московского и всея Руси Кирилла (электронная версия). (Orthodox Encyclopedia - Pravenc.ru).