Op-Ed: 364-Day Calendar Intriguing But Unnecessary
https://www.npr.org/2012/01/02/144583975/op-ed-364-day-calendar-intriguing-but-unnecessary
mentions knuckle counting, viz
http://lifehacker.com/232828/macgyver-tip-use-your-knuckles-to-remember-each-months-days
linkstream2 microblog 
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