VAT rate of 5% is payable on hammer price and at 15% on the buyer's premium
Anonymous sale; Sotheby's, London, 12 November 1970, lot 41.
Please note that the picture was painted in 1881.
R. Feltkamp, Théo Van Rysselberghe, catalogue raisonné, Paris, 2003, no. 1881-016.