Calendar
Free to read here, from Project Gutenberg.
The Fundamental Principles of Old and New World Civilizations
Ancient calendars and constellations
Our Calendar
Fasti
Notes on Certain Maya and Mexican Manuscripts
Remarks upon the solar and the lunar years, the cycle of 19 years, commonly called the golden number, the epact, and a method of finding the time of Easter, as it is now observed in most parts of Europe
