Literatuur
Karl Josef Höltgen, `The ruler between two columns: imperial aspirations and political iconography from the emperor Charles V to William [III] of Orange’, in: Emblem studies in honour of Peter M. Daly / ed. by Michael Bath, Pedro F. Campa, Daniel S. Russell. – Baden Baden : Valentin Koerner, 2002. – XIV, 271 p. : ill. ; 24 cm. – (Saecula spiritalia, ISSN 0343-2009 ; Bd. 41) ISBN 3-87320-441-X, p. 143-168.