Coyne, G. V., Hoskin, M. A., & Pedersen, O. (1983). Gregorian reform of the calendar: Proceedings of the Vatican Conference to commemorate its 400th anniversary, 1582-1982. Pontificia Academia Scientiarum : Specola Vaticana.
Chicago Style (17th ed.) CitationCoyne, George V., Michael A. Hoskin, and O. Pedersen. Gregorian Reform of the Calendar: Proceedings of the Vatican Conference to Commemorate Its 400th Anniversary, 1582-1982. Citt ̉del Vaticano, Europe: Pontificia Academia Scientiarum : Specola Vaticana, 1983.
MLA (8th ed.) CitationCoyne, George V., et al. Gregorian Reform of the Calendar: Proceedings of the Vatican Conference to Commemorate Its 400th Anniversary, 1582-1982. Pontificia Academia Scientiarum : Specola Vaticana, 1983.
Warning: These citations may not always be 100% accurate.