 In the Spanish archives of Simancas ("Archivo General de Simancas") there are, archived, two of his memorials, a sort of "resume" listing their accomplishments which, at the time, soldiers would have to prepare every time they sought promotion.The second one is dated fifteen years after his autobiography and gives further insight into the story of his life.Contreras compiled sailing charts about Mediterranean ports, capes and creeks, marking where all kinds of ships can be repaired and marking the depth of water.