In 1920, the Chilean historian published a comprehensive study of Magellan containing an impressive amount of biographical information, a detailed analysis of the beginning and development of the voyage of circumnavigation, and a remarkable amount of information on the crews of the Armada de Molucca.
In addition, Medina produced the fullest bibliographies yet attainable of books printed at Lima, Mexico and Manila, and a number of memoirs and other minor writings.