This document lists several influential modern artists and their works from the early 20th century, including Alfred Stieglitz, Georgia O'Keefe, Man Ray, Meret Oppenheim, Marcel Duchamp, Ben Shahn, Grant Wood, Thomas Hart Benton, Jackson Pollack, Diego Rivera, Pablo Picasso, and John Heartfield. Many of the works referenced were pioneering in their use of new artistic styles and mediums that pushed the boundaries of traditional art.