Anderson, Scott: New Year’s Revolution: A proposed new calendar would give February an extra week and start every month on a Monday. (Artikkeli osiossa: Leading Edge) University of Toronto Magazine (Toronton yliopiston aikakauslehti), talvella 2011. Toronton yliopisto. Artikkelin verkkoversio. Viitattu 18.2.2023. (englanniksi)
wsj.com
Forelle, Charles: Time and Again, the Calendar Comes Up Short: Sticklers for Symmetry Lament Imperfections in the 400-Year-Old Gregorian System; Earth's Inconvenient Orbit. (Artikkeli osiossa: The Numbers Guy) The Wall Street Journal, 31.12.2009. Artikkelin verkkoversio. Viitattu 18.2.2023. (englanniksi)
