Article Cowham, Mike (1999)
Calendar systems and perpetual calendars. Part 1: Calendar systems. Part 2: Finding Easter. Bulletin of the Scientific Instrument Society (p. 20). (/isis/citation/CBB000080104/) unapi

Article Solan, Olivier de (1999)
La réforme du calendrier dans une question quodlibétique d'Henri de Runen (1444). Bibliothèque de l'École des Chartes (pp. 171-220). (/isis/citation/CBB000080965/) unapi

Article Davies, Christie; Trivizas, Eugene; Wolfe, Roy (1999)
The failure of calendar reform (1922-1931): Religious minorities, businessmen, scientists, and bureaucrats. Journal of Historical Sociology (pp. 251-270). (/isis/citation/CBB000082935/) unapi

Book Poole, Robert (1998)
Time's alteration: Calendar reform in early modern England. (/isis/citation/CBB000081599/) unapi

Book Borst, Arno (1998)
Die karolingische Kalenderreform. (/isis/citation/CBB000078844/) unapi

Article Moreton, Jennifer (1998)
Doubts about the calendar: Bede and the eclipse of 664. Isis: International Review Devoted to the History of Science and Its Cultural Influences (pp. 50-65). (/isis/citation/CBB000077663/) unapi

Article Smith, Mark M. (1998)
Culture, commerce, and calendar reform in colonial America. William and Mary Quarterly (pp. 557-584). (/isis/citation/CBB000081828/) unapi

Article Guérin, René-Guy (1998)
Les horoscopes au XVIIe siècle. XVIIe Siècle (pp. 505-513). (/isis/citation/CBB000081739/) unapi

Chapter Wenskus, Otta (1998)
Columellas Bauernkalender zwischen Mündlichkeit und Schriftlichkeit. In: Gattungen wissenschaftlicher Literatur in der Antike (p. 253). (/isis/citation/CBB000080754/) unapi

Article Sorbello, Alessandra (1998)
Un calendario xilografato per l'anno 1531 (Ulm, Matthias Hoffischer). Gutenberg Jahrbuch (pp. 154-164). (/isis/citation/CBB000079206/) unapi

Book Shimony, Abner (1998)
Tibaldo and the hole in the calendar. Illustrated by Jonathan Shimony. (/isis/citation/CBB000076889/) unapi

Book Duncan, David Ewing (1998)
Calendar: Humanity's epic struggle to determine a true and accurate year. (/isis/citation/CBB000078912/) unapi

Article Chatterjee, S.K. (1998)
Traditional calendar of Myanmar (Burma). Indian Journal of History of Science (pp. 143-160). (/isis/citation/CBB000081136/) unapi

Article Fatoohi, Louay J. (1998)
A computer program for the conversion of Babylonian into Julian dates. Journal for the History of Astronomy (pp. 378-379). (/isis/citation/CBB000076701/) unapi

Article Gaspard, Claire (1998)
L'interdisciplinarité à l'épreuve des almanachs de la fin du siècle. Dix-huitième siècle (pp. 165-177). (/isis/citation/CBB000081779/) unapi

Article Pedroni, Luigi (1998)
Ipotesi sull'evoluzione del calendario arcaico Roma. Papers of the British School at Rome (pp. 39-55). (/isis/citation/CBB000080733/) unapi

Article McCarthy, Dennis D. (1998)
The Julian and modified Julian dates. Journal for the History of Astronomy (pp. 327-330). (/isis/citation/CBB000076713/) unapi

Book Somer, John (1998)
The Kalendarium of John Somer. Edited by Mooney, Linne R.. (/isis/citation/CBB000080966/) unapi

Book Richards, E.G. (1998)
Mapping time: The calendar and its history. (/isis/citation/CBB000080131/) unapi

Book Pérez Higuera, Teresa (1998)
Medieval calendars. (/isis/citation/CBB000080958/) unapi