http://books.google.de/books?id=TxgmLwAACAAJ&dq=The+Work+of+Art+in+the+Age+of+Mechanical+Reproduction&hl=de&ei=hlldTb6TAYfxsgbf_dXRCg&sa=X&oi=book_result&ct=result&resnum=1&ved=0CCoQ6AEwAA