What is more correct to say:
One summer's/winter's day.
One summer/winter day.
For example: "One summer('s) day we decided to walk in the park"
English Language Learners Stack Exchange is a question and answer site for speakers of other languages learning English. It only takes a minute to sign up.Sign up to join this community
The British National Corpus (bnc) has 36 quotes for "summer day", but none for "summer's day", though "summer's day" is in dictionaries. But when "summer" is an element in compound nouns it is mostly summer: summer camp, summer house, summer school, summer time, summer vacation (AmE), summer holiday (BrE). For AmE this may be a bit different, but I don't believe that there is great difference.