Büsing, N., & Klaas, H. (2002). Clay Ketter. artist : Kunstmagazin.
Cita Chicago (17th ed.)Büsing, Nicole, i Heiko Klaas. "Clay Ketter." Artist : Kunstmagazin 2002.
Cita MLA (8th ed.)Büsing, Nicole, i Heiko Klaas. "Clay Ketter." Artist : Kunstmagazin, 2002.
Atenció: Aquestes cites poden no estar 100% correctes.