Gower, Confessio Amatis, 1483 (CCxir)

In this colophon, Caxton identifies himself as the printer and states that it was finished on September 2 in the first year of King Richard III’s reign, 1493. But the first year of Richard’s reign was 1483, and so catalog records provide that as the correct date. (It’s certainly much easier to accidentally slip in an extra “x” to the date than to confuse the first and tenth year of your monarch’s rule.)