This work's protagonists 
This work's protagonists fight with a number of Yanguesans following an incident with a horse, and earlier witnessed Marcela defending herself from a poem written by the lovesick shepherd Chrysostom. One character in this work is led to believe that a wizard named Friston has stolen his library, while another is appointed Governor of Barataria by the Duke. This work's title character is defeated and forced to retire by the Knight of the White Moon, and claims to love the lady Dulcinea. For 10 points, name this novel by Miguel Cervantes featuring characters such as Sancho Panza and a man who famously tilts at windmills.
This work's protagonists fight with a number of Yanguesans following an incident with a horse, and earlier witnessed Marcela defending herself from a poem written by the lovesick shepherd Chrysostom.