Giovanni and Gregorio De Gregori explained

Giovanni and Gregorio ^[1] De Gregori (Latin: Johannes & Latin: Gregorius de Gregoriis) were two Italian brothers from Forlì who worked as printers in Renaissance Venice. They are generally credited with the first attractive type in nonpareil size for a 1498^[2] or 1501^[3] edition of the divine offices.

Gregorio de Gregori is considered to have published the first book printed in Arabic, Kitab salat al-sawai—a book of hours—in 1514.^[4]

Notes and References

1. Contemporaries of Erasmus, p. 126
2. The Inland Printer, Vol. IV, p. 137.
3. The Practice of Typography, p. 67.
4. M. Krek . M. . 1979 . The Enigma of the First Arabic Book Printed from Movable Type . Journal of Near Eastern Studies . 38 . 3 . 203–212 . 10.1086/372742.