It was on a Wednesday.
December 13 1967 was a Wednesday.
January 13, 1967 was a Friday.
October 13 1967 was a Friday.
November 13, 1967, was a Monday.
August 13 1967 was on a Sunday.
March 13, 1967 was a Monday.
February 13 1967 was on a Monday.
13 July 1967 was a Thursday.Thursday
December 13 1956 was a Thursday.
December 13 1999 was on a Monday.
December 13 1985 was on a Friday.
13 December 2001 was a Thursday.