Brushing up on the artists mentioned in this article, here are some great videos about the artists and their art.
Tony Smith
https://www.youtube.com/watch?v=HCg3_p46QaA
Robert Grosvenor
https://www.youtube.com/watch?v=fezrdtH6MNE
Ronald Bladen
https://www.youtube.com/watch?v=c47yVL-IsWY
David Smith
https://www.youtube.com/watch?v=JXfWdgqluUw