Bill Withers is great Sunny, he's got some timeless R&B music. One of the first songs I ever remember loving is Just The Two Of Us when I heard it as a child.
I discovered A Lovely Day in my 20's and I loved that song alot too, it's an got an amazing feeling in the music. Smif N Wessun sampling him for Wreckonize remix was a great thing.
here's an article on him from 1973: read here
I think this might be one of his more slept-on albums, it's a good one though. It's a soulful record with great arrangement and lyrics. My favorite is City Of The Angels.