it was a Sunday [:
January 13, 1974 fell on a Sunday.
August 13, 1974 fell on a Tuesday.
May 13, 1974 was a Monday.
Thurday
Wednesday
Saturday.
Friday
It was a Friday.
13 October 1964 was a Tuesday.
13 October 1978 was a Friday.
13 October 1958 was a Monday.
13 October 1970 was a Tuesday.