Original: The Marcus collections included significant works by Mexican artists Rufino Tamayo , David Alfaro Siqueiros , Diego Rivera , and Rivera 's lesser-known friend and colleague Antonio Ruíz ; the American sculptor Alexander Calder , and American painter Georgia O'Keeffe .
Simplified: His favorite artists from Mexico were Rufino Tamayo , David Alfaro Siqueiros , Diego Rivera , and Antonio Ruíz .