Coba jelasin Lihat pula dari Computus dong

Blackburn, Bonnie, and Holford-Strevens, Leofranc. (2003). The Oxford Companion to the Year: An exploration of calendar customs and time-reckoning. (First published 1999, reprinted with corrections 2003.) Oxford: Oxford University Press.

Borst, Arno (1993). The Ordering of Time: From the Ancient Computus to the Modern Computer Trans. by Andrew Winnard. Cambridge: Polity Press; Chicago: Univ. of Chicago Press.

Clavius, Christopher (1603): Romani calendarij à Gregorio XIII. P. M. restituti explicatio. In the fifth volume of Opera Mathematica (1612). This  includes page images of the Six Canons and the Explicatio

Constantine the Great, Emperor (325): Letter to the bishops who did not attend the first Nicaean Council; from Eusebius' Vita Constantini. English translations:

Coyne, G. V., M. A. Hoskin, M. A., and Pedersen, O. (ed.) Gregorian reform of the calendar: Proceedings of the Vatican conference to commemorate its 400th anniversary, 1582-1982, (Vatican City: Pontifical Academy of Sciences, Specolo Vaticano, 1983).

Dyonisius Exiguus (525): Liber de Paschate. On-line: (full Latin text) and (table with Argumenta in Latin, with English translation)

Eusebius of Caesarea, The History of the Church, Translated by G. A. Williamson. Revised and edited with a new introduction by Andrew Louth. Penguin Books, London, 1989.

Gibson, Margaret Dunlop, The Didascalia Apostolorum in Syriac, Cambridge University Press, London, 1903.

Gregory XIII (Pope) and the calendar reform committee (1581): the Papal Bull Inter Gravissimas and the Six Canons. On-line under: "Les textes fondateurs du calendrier grégorien", with some parts of Clavius's Explicatio

Schwartz, E.,  Christliche und jüdische Ostertafeln, (Abhandlungen der königlichen Gesellschaft der Wissenschaften zu Göttingen. Pilologisch-historische Klasse. Neue Folge, Band viii.) Weidmannsche Buchhandlung, Berlin, 1905.

Stern, Sacha, Calendar and Community: A History of the Jewish Calendar Second Century BCE - Tenth Century CE, Oxford University Press, Oxford, 2001.

Wallis, Faith., Bede: The Reckoning of Time, (Liverpool: Liverpool Univ. Pr., 1999), pp. lix-lxiii.

Weisstein, Eric. (c. 2006) "Paschal Full Moon" in World of Astronomy.

A discussion of the Nicene Council's Easter decision and of how some commentators exaggerate the scope of the Council's decision

Improved algorithm by Dr. Heiner Lichtenberg (in German) (in English)