Signed in pencil u.l. Cyril E. Power E. P. 3; in graphite l.l. Final Specimen; verso, l.l.: Final Speciment
Possibly sold Christie's, January 15, 1990; Leslie and Johanna Garfield (New York); their gift to MFA, December 27, 2002.
Gift of Leslie and Johanna Garfield in honor of Barbara Stern Shapiro
Courtesy EB Power & Osborne Samuel Ltd, London