JAPAN (1992) Accountant's emblem*. 50th anniversary of CPA system overprinted MIHON (specimen). Scott No 2149, Yvert No 2014. Not easy to find!
AVAILABLE AT $20
GERMANY (1959) Adam Riese*. MUSTER (specimen) overprint. Scott No 799.
AVAILABLE AT $15
GERMANY (1966) Gottfried Leibniz*. MUSTER (specimen) overprint. Scott No 962.
AVAILABLE AT $15
GERMANY (1973) Schickard's calculator*. MUSTER (specimen) overprint. Scott No 1123.
AVAILABLE AT $15
GERMANY (1977) Graph*. MUSTER (specimen) overprint. 200th birthday of Gauss. Scott No 1246.
AVAILABLE AT $15
GERMANY (1980) Gottfried Leibnitz*. Specimen (overprinted MUSTER). Scott No 1329, Yvert No 894.
AVAILABLE AT $15
GERMANY (1984) Friedrich Bessel*. Graph of Bessel function*. Specimen (overprinted MUSTER). Scott No 1422, Yvert No 1048.
AVAILABLE AT $15
GERMANY (1992) Adam Riese, mathematician. Scott No 1748. "MUSTER" (Specimen) overprint. Father of modern calculating.
AVAILABLE AT $15
GERMANY (1996) Leibnitz*. Treatise*. Overprinted MUSTER (specimen). Scott No 1933, Yvert No 1697.
AVAILABLE AT $15
GERMANY (1998) Squares*. Numbers*. MUSTER (specimen) overprint. International Congress of Mathematics. Scott No 2010, Yvert No 1837.
AVAILABLE AT $15