McClendon 1996, tr. 4 McClendon, Charles B. (1996). “Aachen: Buildings: Palatine Chapel: Architecture”. Trong Turner, Jane; Brigstocke, Hugh (biên tập). The Dictionary of Art. 1: A to Anckerman. New York, NY: Grove. tr. 2–4. ISBN0-19-517068-7. LCCN96013628.
McClendon 1996, tr. 2 McClendon, Charles B. (1996). “Aachen: Buildings: Palatine Chapel: Architecture”. Trong Turner, Jane; Brigstocke, Hugh (biên tập). The Dictionary of Art. 1: A to Anckerman. New York, NY: Grove. tr. 2–4. ISBN0-19-517068-7. LCCN96013628.
McClendon 1996, tr. 2 McClendon, Charles B. (1996). “Aachen: Buildings: Palatine Chapel: Architecture”. Trong Turner, Jane; Brigstocke, Hugh (biên tập). The Dictionary of Art. 1: A to Anckerman. New York, NY: Grove. tr. 2–4. ISBN0-19-517068-7. LCCN96013628.
McClendon 1996, tr. 3 McClendon, Charles B. (1996). “Aachen: Buildings: Palatine Chapel: Architecture”. Trong Turner, Jane; Brigstocke, Hugh (biên tập). The Dictionary of Art. 1: A to Anckerman. New York, NY: Grove. tr. 2–4. ISBN0-19-517068-7. LCCN96013628.
Grimme 1972, tr. 10 Grimme, Ernst Günther (1972). Der Aachener Domschatz [The Aachen Cathedral Treasury]. Aachener Kunstblätter [Written Works on Aachen] (bằng tiếng Đức). Düsseldorf, Germany: L. Schwann. LCCN72353488.