It was a Wednesday.
May 13th, 1981 fell on a Wednesday. The following year, it fell on a Thursday.
October 13 1981 was a Tuesday.
October 13, 1981 was on a Tuesday.
December 13, 1981 fell on a Sunday.
April 13, 1981 fell on a Monday.
August 13th 1981 was a Thursday.
Sunday
A Tuesday
It was a Friday.
Tuesday.
It was a Friday.
23rd May 1981, was a Saturday.