Firman of Karamanoğlu Mehmet Bey
Mehmet Bey's firman was the decree of Mehmet I of Karaman (Karamanoğlu Mehmet), a vizier of Suljuks, declaring that the official language of Seljuks was Turkish. Mehmet Beg or Mehmet Bey of Karaman (Turkish: Karamanoğlu Mehmet Bey), also known as Shams al-Din Mehmed Beg was the third ruler of the Karamanids.
Source: Wikipedia — Firman of Karamanoğlu Mehmet Bey (CC BY-SA 4.0)