Poster for the event "A Mirror on Which to Dwell" featuring The East Coast Contemporary Ensemble performing Elliott Carter's Settings of Elizabeth Bishop's Poems. The poems were introduced and read by Lloyd Schwartz. This event was held in Tilton Hall at Clark University on April 21, 2011. Photos from this event can be found here.
These are currently the best available versions of these posters.
Some the artists who helped design these posters include Nina Borland, Jasper Boyd, Isabel Miranda, and Sampson Wilcox. This is the current extent of our knowledge regarding the Henry J. Leir poster designers.
Clark University, "A Mirror on Which to Dwell" (2011). Event Posters. 10.