Poems with Eigner numbers composed of 2 lowercase letters (except with L), such as ac, often enclosed in double brackets, sometimes accompanied by other punctuation marks, 1959 - 1966, Box: 4, Section D. Larry Eigner poems and papers, MS 39. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/239788 Accessed May 22, 2024.