Entre otros, podemos destacar: "Manuale tipographicum" (1954); "About alphabets, some marginal notes on type design" (1960); "Typographische Variationen" (1963); "Hunt Roman, the birth of a type" (1965); "Orbis Typographicus" (1980); y "Hermann Zapf and his design Philosophy", Society of Typographic Arts, Chicago (1987).