Question: When did Juan Alfonso Pérez De Guzmán, 6Th Duke Of Medina Sidonia's father die?
Sentence (from "Juan Alfonso Pérez de Guzmán, 3rd Duke of Medina Sidonia"): His mother is known as Leonor de Mendoza y Ribera, although he was known by using as his second name "Afan de Ribera".
Relevant evidence: No