Singer Mercedes ' ` ` lived her 74 years to the fullest , '' her son says . Admired and respected throughout the world , Mercedes is recognized as a symbol of our cultural heritage that will represent us forever , '' the Web site said . She had suffered from liver , kidney and heart ailments , Washington Post says . ` ` Her voice always carried a profound sense of social engagement , '' her site says . Concert to be held Sunday at the Congress of the Nation in Buenos Aires .
Singer Mercedes ' ` ` lived her 74 years to the fullest , '' her son says . She had suffered from liver , kidney and heart ailments , Washington Post says . ` ` Her voice always carried a profound sense of social engagement , '' her site says . Concert to be held Sunday at the Congress of the Nation in Buenos Aires .