“Gregory of Tours, monastic timekeeping, and Early Christian attitudes to astronomy” by Stephen McCluskey
Isis 81 (1990): 8–22
“Astronomy, time, and churches in the Early Middle Ages” by Stephen McCluskey
in Marie-Therese Zenner, ed., Villard’s Legacy: Studies in Medieval Technology, Science and Art in Memory of Jean Gimpel (Aldershot: Ashgate), 197–210.
Time, Astronomy, and Calendars by Charles Burnett and Sacha Stern