Complex sentence: His own chronicle covered the period of 1391 to 1423, but survives only in excerpts quoted by the 16th-century chroniclers Andreas Angelus and Peter Hafftiz.
Split into simpler sentences: His own chronicle covered the period of 1391 to 1423. The text survives only in excerpts quoted by the 16th-century chroniclers Andreas Angelus and Peter Hafftiz.