Works of art that use ladders

Works of art that use ladders:
 * Thomas Kilpper, Anemonevej surprises (2012)
 * Martin Puryear, Ladder for Booker T. Washington (1996)
 * Jonathan Borofsky, Walking to the Sky (2004)
 * Leandro Erlich, Window and Ladder (PS1 New Orleans, 2008)
 * Joseph Beuys, Scala Napoletana(1985)
 * Vito Acconci, 20 Foot Ladder for Any Size Wall(1979-81)
 * Alighiero Boetti, ladder and chair, A-frame (1966)
 * Michael Chrisman, Christmas At Innovation Drive (2011)
 * Daniel Douke, Ace, Acrylic on Masonite (1979)