MLA

Polo, Marco, 1254-1323?, author. Incipit p[ro]logus i[n] libro d[omi]ni marci pauli de veneciis de co[n]suetudinibus et co[n]dicionibus orientaliu[m] regionu[m].. [approximately 1483-1485]. https://collections.library.yale.edu/catalog/33488300.

APA, 6th edition

Polo, Marco, 1254-1323?, author. ([approximately 1483-1485])[Incipit p[ro]logus i[n] libro d[omi]ni marci pauli de veneciis de co[n]suetudinibus et co[n]dicionibus orientaliu[m] regionu[m].]. https://collections.library.yale.edu/catalog/33488300.