Karsten Schubert, London
PaceWildenstein, New York
Enron Collection, Houston
Sale: Phillips de Pury & Luxembourg, New York, Contemporary Art, 15 May 2003, Lot 31
Acquired directly from the above by the present owner

London, Karsten Schubert, Bridget Riley: Colour Studies, 1993
London, Waddington Galleries, Bridget Riley: Recent Paintings and Gouaches, 1996, p. 19, no. 2, illustrated in colour 
Krefeld, Museum Haus Esters and Kaiser Wilhelm Museum, Bridget Riley: New Work, 2002, p. 171, illustrated
New York, PaceWildenstein, Bridget Riley: Paintings 1982-2000 and Early Works on Paper, 2000, p. 46, illustrated
Berlin, Galerie Max Hetzler, Bridget Riley: Paintings and Other Related Work 1983-2010, 2011, pp.34-5, illustrated  in colour

Trevor Lamb and Janine Bourriau, Colour: Art and Science, London, 1995, illustration of a detail on the cover

Colour: The colours in the catalogue illustration are fairly accurate, although the overall tonality is brighter in the original. Condition: This work is in very good condition. There is extremely minor wear to all four corner tips with a few specks of associated paint loss and a few specks along the lower edge and one below the top right corner. There are two very faint rub marks on the right edge: one towards the centre and one towards the lower right corner. No restoration is apparent when examined under ultra-violet light.
"In response to your inquiry, we are pleased to provide you with a general report of the condition of the property described above. Since we are not professional conservators or restorers, we urge you to consult with a restorer or conservator of your choice who will be better able to provide a detailed, professional report. Prospective buyers should inspect each lot to satisfy themselves as to condition and must understand that any statement made by Sotheby's is merely a subjective, qualified opinion. Prospective buyers should also refer to any Important Notices regarding this sale, which are printed in the Sale Catalogue.
NOTWITHSTANDING THIS REPORT OR ANY DISCUSSIONS CONCERNING A LOT, ALL LOTS ARE OFFERED AND SOLD AS IS" IN ACCORDANCE WITH THE CONDITIONS OF BUSINESS PRINTED IN THE SALE CATALOGUE."

"I saw that the basis of colour is its instability. Instead of searching for a firm foundation, I realised that I had one in the very opposite. That was solid ground again, so to speak, and by accepting this paradox I could begin to work with the fleeting, the elusive, with those things which disappear when you actually apply your attention hard and fast."

(the artist interviewed by Michael Craig-Martin in: Robert Kudielka, Ed., Dialogues on Art, London 1995, p. 56)