"Princess Dorothea of Schleswig-Holstein-Sonderburg-Glücksburg (28 September 1636 – 6 August 1689), was Duchess consort of Brunswick-Lüneburg by marriage to Christian Louis, Duke of Brunswick-Lüneburg, and Electress of Brandenburg by marriage to Frederick William, Elector of Brandenburg, the "Great Elector"." - (en.wikipedia.org 20.11.2019)
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