"Etymologiae" was the most used textbook throughout the Middle Ages. It was so popular that it was read in place of many of the original classical texts that it summarized, so these ceased to be copied and were lost. It was cited by Dante Alighieri, who placed Isidore in his "Paradiso", quoted by Geoffrey Chaucer, and mentioned by the poets Boccaccio, Petrarch and John Gower. Among the thousand-odd surviving manuscript copies is the 13th-century "Codex Gigas"; the earliest surviving manuscript, the "Codex Sangallensis", preserves books XI to XX from the 9th century. "Etymologiae" was printed in at least ten editions between 1472 and 1530, after which its importance faded in the Renaissance. The first scholarly edition was printed in Madrid in 1599; the first modern critical edition was edited by Wallace Lindsay in 1911.