title: Guido of Arezzo
context: Guido of Arezzo (also Guido Aretinus, Guido Aretino, Guido da Arezzo, Guido Monaco, Guido d'Arezzo, or Guy of Arezzo also Guy d'Arezzo) (991/992 – after 1033) was an Italian music theorist of the Medieval era. He is regarded as the inventor of modern musical notation (staff notation) that replaced neumatic notation. His text, the Micrologus, was the second most widely distributed treatise on music in the Middle Ages (after the writings of Boethius).
question: When did Guido of Arezzo live?
answers: 991/992 – after 1033