www.lemonde.fr/voyage/article/2010/10/13/philadelphie-la-cite-qui-aime-les-arts_1423520_3546.html muralarts.org/ http://www.brynmawr.edu/sociology/facstaff.html http://www.cloud9living.com/philadelphia/mural-art-walking-tour "......À l'origine, le Mural...