May 20 1980 was a Tuesday.
20 January 1980 was a Sunday.
December 20, 1980 was on a Saturday.
Friday
October 20th 1980 was a Monday.
20 May 1942 was a Wednesday.
May 20 1971 was a Thursday.
May 20, 1955, was a Friday
May 20 1965 was on a Thursday.
May 20 2010 was a Thursday.
May 20, 2011 was a Friday.
May 20 1946 was on a Monday.
May 20, 1989 was a Saturday.