The author of the linked paper, Philip Wadler, is just phenomenal.
http://homepages.inf.ed.ac.uk/wadler/
>"I was a principal designer of Haskell. With Simon Marlow, I developed
a type tool for Erlang. I am a founding member of IFIP WG 2.8 Functional
Programming, and served as editor-in-chief of the Journal of Functional
Programming."
