The Theatre, by Nozière. At the Vaudeville. The Three Anabaptists, by Alexandre Bisson and Berr de Turique. [...] Mlle de Mornand, whose golden hair sparkles beneath a barrister's toque, gives a swaggering performance in the exquisite scene in which her aunt reproaches her for loitering with the probationers, behind the statue of Berryer.
Gil Blas, 17 September 1904.
According to Philip Kolb: Proust writes a "cameo" about Louisa de
Mornand for inclusion in Gil Blas and asks Antoine de Bibesco
to have it published. See note
for Dec 1904.
Nozière was the pseudonym under which Fernand Weyl (1874-1931) wrote as theatre critic for Gil Blas, so it is uncertain whether this was written by Proust or Weyl. The full review is actually 3 columns in length, but presumably this mention was included at Proust's request.