Sean Scully, Untitled 11.7.88, 1988, Pastel and charcoal on paper, The Museum of Modern Art, New York. https://dartabase.art/cite/moma/35699

Sean Scully, Untitled 7.12.90, 1990, Pastel and charcoal on paper, The Museum of Modern Art, New York. https://dartabase.art/cite/moma/34819