For a similar blue glass example from the J. T. Royer collection in the Rijksmuseum, Amsterdam see Pieter C. Ritsema van Eck and Henrica M. Zijlstra-Zweens, Glass in the Rijksmuseum, Amsterdam, 1993, Vol. I, p. 287, no. 404. Jean Théodore Royer (1737-1808) of The Hague was clerk to the Court of Holland, Zeeland and west Friesland (1767-1795) and was a noted collector, in 1814 his widow gave his collection of applied arts to King William I.