Chi p’u (Google Books ⧉, Amazon ⧉, Bookshop ⧉)

The Travels of Marco Polo

The Chi p’u, a treatise on paper, written by Su I-kien toward the close of the tenth century, enumerates among the various sorts of paper manufactured during his lifetime paper from the bark of the mulberry tree (sang p’i) made by the people of the north.[3]