Luxemburger Wort, Jg. 127, n°149, Luxembourg, Editions Saint-Paul, 1988, pp. 3. ; Luxemburger Wort, n°150, Luxembourg, Editions Saint-Paul, 1974, pp. 3 ; Luxemburger Wort, n°151, Luxembourg, Editions Saint-Paul, 1974, pp. 3. ; Luxemburger Wort, n°152, Luxembourg, Editions Saint-Paul, 1974, pp. 3.