The Festal Epistles of S. Athanasius, A Library of Fathers of the Holy Catholic Church, anterior to the division of the East and West, translated by Burgess, Henry, 1854, pp. xv–xxvi
The term "Chaldean order" is modern, used e.g. in Popular Science, January 1895, p. 335, but there is no evidence this order is actually taken from Babylonian astrology; rather, it seems to be a Hellenistic innovation of the 2nd century BC; see Eviatar Zerubavel, The Seven Day Circle: The History and Meaning of the Week, University of Chicago Press, 1989 [1985],
p. 14.
Nerone Caesare Augusto Cosso Lentuol Cossil fil. Cos. VIII idus Febr(u)arius dies solis, luna XIIIIX nun(dinae) Cumis, V (idus Februarias) nun(dinae) Pompeis. Robert Hannah, "Time in Written Spaces", in: Peter Keegan, Gareth Sears, Ray Laurence (eds.), Written Space in the Latin West, 200 BC to AD 300, A&C Black, 2013, p. 89.
Giuseppe Bezza, "Representation of the Skies and the Astrological Chart" in: Brendan Dooley (ed.) A Companion to Astrology in the Renaissance, Brill's Companions to the Christian Tradition, 2014, p. 70.
Steven Vanden Broecke, The Limits of Influence: Pico, Louvain, and the Crisis of Renaissance Astrology, volume 4 of History of science and medicine library: Medieval and early modern science, BRILL, 2003, p. 130.
Falk, Michael (19 March 1999). "Astronomical names for the days of the week". Journal of the Royal Astronomical Society of Canada. 93 (1999–06): 122–133. Bibcode:1999JRASC..93..122F.
The day is divided into two parts; the day (time between sunrise and sunset) and the night (time between sunset and tomorrow's sunrise). Each part of the day is then divided into 12 equal parts, for a total of 24 (unequal) hours.
The further the location is from the equator; and the closer the date is to the solstices (as opposed to the equinoxes); the greater the difference in length between the length of the planetary hours and the clock hours.
Barrett, Francis (1989) [First printed in 1801]. "Book II. Part IV. The Magic and Philosophy of Trithemius of Spanheim". The Magus (First Carol Publishing Group ed.). New York: Carol Publishing Group. pp. 139–140. ISBN0-8065-0462-5.
