The given date was a Sunday.
Sunday.
July 31 1970 was on a Friday.
Tuesday
Monday.
31st october 1970 was a Saturday.
August, 31st, 1970, was a Monday,
31 May 1958 was a Saturday.
May 31 1967 was a Wednesday.
May 31 1966 was a Tuesday.
May 31 1947 was a Saturday.
May 31, 1976 was a Monday.
May 31 2010 was a Monday.