Charles Olson on Cy Twombly
"Cy Twombly," (1952) in Olson, Charles, Donald Merriam Allen, Benjamin Friedlander, and Robert Creeley. Collected Prose. Berkeley (Calif.): University of California press, 1997, 175-8. Read it here.
"For Cy Twombly Faced with His First Chicago & N.Y. Shows," in Olson, Charles, and George F. Butterick. The Collected Poems of Charles Olson: Excluding the Maximus Poems. Berkeley: University of California Press, 1987, 244. Read it here.