Klaus Ertz
Klaus Ertz (born 1945) is a German art historian specializing in the Brueghel family of artists and their workshop.Ertz was born in Homburg and is best known for his catalogues raisonnés on Jan Brueghel the Elder, his son Jan II, his brother Pieter Brueghel the Younger, Josse de Momper, Marten van Cleve, Jan van Kessel, David Vinckboons, Josef van Bredal and Adriaen van Stalbemt. Ertz works as a private art consultant for various institutions in the art market. He and his wife Christa Nitze-Ertz own the art printing house Luca-Verlag in Lingen(Ems) that publishes books about Flemish paintings of the 16th and 17th century. Provided by Wikipedia
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