Chicago Review has some interesting letters between Ed Dorn and Tom Raworth and Dorn and Olson in 1961.
So far they are really interesting.
Raworth is really funny. I did not realize he had such a complex family background. He says his mother was Irish "from a Dublin family of anti-British bomb throwers" and his father was from "a poor London family." Raworth left school at sixteen. from what I can gather he is largely self-educated.
This latest issue also has some critical essays on Dorn. Jennifer Dunbar Dorn chronicles Dorn in the 80's.
Lisa Jarnot reviews Tom Clark's biography of Dorn.
Also some good poems by Chris Stroffolino, Peter Riley, Mark McMorris, and Christy Garren. An interview with Eleni Sikelianos.
Chicago Review is a good mag for solid contextuality and historical breadth.