Klaus-Jürgen Sembach, Henry Van de Velde, New York, 1989, pp. 44-45 for the original model
Amy F. Ogata, Art Nouveau and the Social Vision of Modern Living: The Belgian Artists in a European Context, Cambridge, 2001, p. 97 for the original model
Thomas Föhl, Sabine Walter, Werner Adriaenssens, Henry van de Velde: Passion, Function, Beauty 1863-1957, Tielt, 2014, pp. 70, 77, 96, 114