Columbia subject headings:
Pedro I, King of Castile and Leon, 1334-1369--In literature.
Vega, Lope de, 1562-1635--Characters--Pedro I.
Harvard subject headings:
Pedro I, King of Castile and Leon, 1334-1369--In literature.
Vega, Lope de, 1562-1635--Characters--Pedro I.
Princeton subject headings:
Pedro I, King of Castile and Leon, 1334-1369--In literature.
Vega, Lope de, 1562-1635--Characters--Pedro I.