Referenced In

The Travels of Marco Polo
by Marco Polo, da Pisa Rusticiano

"GURUN. Gurun = Kurun = Chinese K’u lun = Mongol Urga."

The Travels of Marco Polo
by Marco Polo, da Pisa Rusticiano

"… the Chinese (Manchu) agent at Urga has not had any control over the Little Bucharia Cities."