See his letters, ed. by R. S. Magurn (1955); selected drawings (2 vol., 1959) and oil sketches (2 vol., 1980), both ed. by J. S. Held ; biographies by N. B. Gerson (1973) and K. Downes (1984); studies by J. Fletcher (1969), J. R. Martin (1969), J. Thuillier (tr. 1970), and J. Held (1981).
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.