Referenced In

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

"…Lieutenant Garnier found cowries nowhere in use north of Luang Prabang..."

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

"mentioned as Lanchang (or Luang Prabang) in the list of Siamese or Laotian countries"