D’Achery, Lucas. Spicilegium. Tom. II. fol. Paris, 1723. [This contains the Hieronymian Martyrology; the metrical Martyrology attributed to Bede; the Martyrology known as Gellonense (from the monastery at Gellone, on the borders of the diocese of Lodève in the province of Narbonne), assigned to about A.D. 804; the metrical Martyrology of Wandalbert the deacon, of the diocese of Trèves, about A.D. 850; and an old Kalendar (A.D. 826) from a manuscript of Corbie.]
Duchesne, L. Origines du Culte chrétien. 3rd Ed. 8vo. Paris, 1902. [There is an English translation by M. L. McClure, London (S.P.C.K.), 1903. The merits of Duchesne are so generally recognised that it is unnecessary to speak of them here.]
Grotefend, H. Zeitrechnung des deutschen Mittelalters und der Neuzeit. 4to. 2 vols. Hanover, 1891, 1892-8. [Besides exhibiting in full a large collection of Kalendars of Dioceses and Monastic Orders, not only of Germany, but also of Denmark, Scandinavia, and Switzerland, this work contains an index of Saints marking their days in various Kalendars, including certain Kalendars of England. There is also a Glossary, explaining both technical terms and the words of popular speech and folk-lore in connexion with days and seasons.]
Hampson, R. T. Medii Ævi Kalendarium, or dates, charters, and customs of the middle ages, with Kalendars from the tenth to the fifteenth century; and an alphabetical digest of obsolete names of days: forming a Glossary of the dates of the middle ages, with Tables and other aids for ascertaining dates. 8vo. 2 vols. London, 1841. [The first volume is mainly occupied with ‘popular customs and superstitions’; but it also contains reprints of various Anglo-Saxon and early English Kalendars. The second volume is given over wholly to a useful, though occasionally somewhat uncritical glossary.]
Hospinian, Rudolph. Festa Christianorum, hoc est, De origine, progressu, ceremoniis et ritibus festorum dierum Christianorum Liber unus (folio). Tiguri, 1593. [This is a work of considerable learning for its day, written from the standpoint of a Swiss Protestant. A second edition, in which replies are made to the criticisms of Cardinal Bellarmine and Gretser, appeared, also at Zurich, and in folio, in 1612.]
Ideler, Ludwig. Handbuch der mathematischen und technischen Chronologie. 8vo. 2 vols. Berlin, 1825-26. [Ideler was Royal Astronomer and Professor in the University of Berlin. His discussion of the Easter cycles cannot be dispensed with. This and his account of the computation of time in the Christian Church will be found in Vol. 2 (pp. 175-470). The Gregorian reform is well dealt with.]
Kellner, K. A. Heinrich. Heortology: a history of the Christian Festivals from their origin to the present day. Translated from the second German edition. 8vo. London, 1908. [Dr Kellner is Professor of Catholic Theology in the University of Bonn. An interesting and useful volume, though occasionally exhibiting, as is not unnatural, marked ecclesiastical predilections. It contains prefixed a useful bibliography.]
Lietzmann, H. Die drei ältesten Martyrologien. E. tr. 8vo. Cambridge, 1904. [This little pamphlet of 16 pages exhibits conveniently the texts of (1) what is variously known as the Bucherian, or Liberian, or Philocalian Martyrology, (2) The Martyrology of Carthage, and (3) Wright’s Syrian Martyrology.]
Maclean, Arthur John (Bishop of Moray). The article ‘Calendar, the Christian’ in Hastings’ Dictionary of Christ and the Gospels [admirable, generally, for the early period.]