Thiele II, p. 269-270 (Thiele here refers to a relief with the same subject from 1812, which was in Thorvaldsen’s studio, but which does not form part of the museum as it was not considered to be an original work. See Thiele 1831, p. 138, tavle LXXVII. The relief is not known today).
Else Kai Sass: Thorvaldsens Portrætbuster, Copenhagen, Vol. I, p. 176, 238, 242, 307.