 Laurence Bergreen gave due recognition of de Mafra's document in Bergreen's 2003 work titled "Over the Edge of the World, Magellan's Terrifying Circumnavigation of the Globe".It is this document that makes his information an incomparably important geographical testimony that unlocks the mystery of the island of Mazaua.De Mafra wrote that Magellan's port was an isle with a circumference of 3-4 leagues or 9-12 nautical miles.