Who is the oldest publishing house?

Could someone help complete a list of the top, say 25 oldest and still operating publishing houses? Any oldest that I may have missed?

1. Schwabe

"Founded in 1488 by Johannes Petri and is the oldest publishing house still in business" (http://en.wikipedia.org/wiki/Basel).

2. Cambridge University Press (UK, 1534)

(http://en.wikipedia.org/wiki/Cambridge_University_Press)

3. Brill (The Netherlands, 1683)