Juan de Borja y Castro was a nobleman and diplomat; he was the third son of San Francisco de Borja y Aragón, IV Duke of Gandía. He was the dedicatee of the manuscript B-Bc 27086, compiled in Vienna between 1577 and 1579, while Juan de Borja, I Count of Mayalde, served as mayordomo mayor of the Empress Dowager Maria of Austria, Philip II's sister and widow of Maximillian II. Juan de Borja was the oncle of the Duke of Lerma.
According to Thomas W. Bridges, Antonio Blado (b Asola, nr Mantua, 1490 — d Rome, 1567) printed more than 1200 editions in Rome between 1516 and 1567; he was, after Valerio Dorico, the second Roman printer to print music from movable type in a single impression. "Blado's heirs included his widow Paola (d 1588) and sons Paolo (d 1594) and Stefano (d 1585). The latter's marriage to Livia Dorico linked the Blado firm with one of its most important competitors (as had daughter Agnese's marriage to Giovanni Osmarino Gigliotti).... After Paolo's death the business was continued until 1609 by Paolo's widow Porzia (d 1624) and by her daughter Isabella and son-in-law Geremia Guelfi until 1626, although not under the Blado name after 1609".
The books published in Venice by the French printer and composer Antonio [Antoine] Gardano appear below in the "List of related sources"; the books with compositions by him appear here under "Sources".