Mary Pershall, who is also "Susan Shelley," is an author of a number of historical romances, including a series about the family of 
William Marshal:
-  A Shield of Roses (©1984) about Sir Richard fitzGilbert de Clare and Lady Eve MacMurrough, the parents of Isabel de Clare[?]
-  Dawn of the White Rose (©1985) about William Marshal and Isabel de Clare[?], the parents of William fitzWilliam Marshal
-  A Triumph of Roses (©1986) about William fitzWilliam Marshal and Eleanor Plantagenet, daughter of King John and sister of King Henry III
-  Roses of Glory (©1987) about the fictional Giles, son of William fitzWilliam Marshal
 
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