Tolong jelaskan mengenai Silsilah dari Alfonso VI dari Kastilia

This entry incorporates public domain text originally from the 1911 Encyclopædia Britannica. The Kingdom of León-Castilla under King Alfonso VI, 1065-1109, by Bernard F. Reilly (Princeton University Press, 1988): full text online at LIBRO.

Portugal, A Country Study'', by Louis R. Mortimer, ed. Washington, D.C.: Library of Congress, 1993.