Crawford, A. (2010). Yorkist lord: John Howard, Duke of Norfolk, c.1425-1485. Continuum.
Chicago-čujuhus (17. p.)Crawford, Anne. Yorkist Lord: John Howard, Duke of Norfolk, C.1425-1485. London: Continuum, 2010.
MLA-čujuhus (9. p.)Crawford, Anne. Yorkist Lord: John Howard, Duke of Norfolk, C.1425-1485. Continuum, 2010.
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