FRANCE (2001) Fermat*. Equations*. Stage die proof in blue signed by the engraver LAVERGNE. Scott No 2836, Yvert No 3420.
AVAILABLE AT $175
MONACO (1973) Pascal*. Compass and Triangle*. Scott No 875. Yvert No 924. Die Proof in brown signed by the artist LAMBERT and the engraver GUILLAUME.
AVAILABLE AT $160