Götze, Heinz
Castel del Monte : geometric marvel of the Middle Ages
Prestel, 1998
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Baring-Gould, Sabine
Curious myths of the middle ages
Longman, 1906
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Salzman, L.F.
English life in the middle ages
Oxford University Press, 1955
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Coote, Stephen
English literature of the middle ages
Penguin Group, 1988
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Hoyt, Robert S.
Europe in the middle ages
Harcourt, Brace & World, 1966
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