Written in pencil on verso: "J.N. Senior, Drawing for Portland Vase."
Displayed in the exhibition titled "Reflecting antiquity : modern glass inspired by ancient Rome" held at the Getty Villa in Pacific Palisades, California, October 18, 2007-January 14, 2008 and then in the Changing Exhibitions Gallery at The Corning Museum of Glass, February 15-May 27, 2008.
Published in English cameo glass in the Corning Museum of Glass, by David Whitehouse (CMOG, 1994, fig. 13).
Published in Cameo glass : masterpieces from 2000 years of glassmaking, by Sidney Goldstein (CMOG, 1982, fig. 17).
Published in Reflecting antiquity : modern glass inspired by ancient Rome (CMOG, 2007, p. 82-83, 126-127).
Acquired as part of the Juliette K. Rakow estate, RR18242, Oct. 14, 1992. Dr. Rakow acquired items from Kenneth Northwood, a descendant of John Northwood, June 1977.