Columbia subject headings:
Peru--Foreign relations--Spain.
Peru--History--Spanish question, 1864.
Spain--Foreign relations--Peru.
Harvard subject headings:
Peru--Foreign relations--Spain.
Peru--History--Spanish question, 1864.
Spain--Foreign relations--Peru.
Princeton subject headings:
Peru--Foreign relations--Spain.
Peru--History--Spanish question, 1864.
Spain--Foreign relations--Peru.