A similar but slightly smaller dyptich is illustrated in D. Gaborit Chopin, Ivoires Médiévaux Ve-XVe siècle, Paris 2003, cat. no. 207, p. 471.
The typical composition used for the nativity can be found on several small ivory panels from the 14th century. Op. Cit., cat. nos. 203 and 203a, p. 467, cat. no. 204a, p. 467, nos. 206 and 206a, p. 470 and no. 207, p. 471.