December 21, 1966 was a Wednesday.
Wednesday
It was a Saturday.
It was a Monday.
December 17, 1966 was a Saturday.
1966 started on a Saturday, and was not a leap year, so 21st October was a Friday.
December 21st 1965 was a Tuesday.
December 21st 2012 is a Friday.
December 2, 1966 fell on a Friday.
December 15, 1966 fell on a Thursday.
December 20, 1966 fell on a Tuesday.
It was a Wednesday
December 21st 2009 is a Monday.