Jonah 3 - Sutcliffe's Commentary on the Old and New Testaments

Jonah 3:4. Yet forty days, and Nineveh shall be overthrown. The LXX read “three days,” and they are followed by most of the Greek fathers. But three days is thought to be an error of the scribe, for the Hebrew, the Chaldaic, Aquila, Symmachus, and Theodotian have forty days. Justin Martyr also, in his dialogue with Trypho the Jew, reads the same.