POLOGNE (1955) Chopin*. Yvert No 794. Scott No 666. 5ème concours international "Frédéric Chopin" de piano à Varsovie. Essai de couleur, en sépia, bord de feuille, surchargé "PROBA" (Epreuve) **. Difficile à trouver!]
AVAILABLE AT $70
MONACO (1975) Johann Strauss*. Full sheet of 30 trial color proofs. Yvert No 1042, Scott No 998.
AVAILABLE AT $475
MONACO (1969) Hector Berlioz*. Trial color proofs in full sheet of 30 with printers color codes in margin. Scott No C75, Yvert No PA93.
AVAILABLE AT $600