Used with
permission of Maiken Naylor, University at Buffalo, Buffalo, NY, USA,
http://ublib.buffalo.edu/libraries/units/sel/exhibits/stamps
Sonia Kovalevskaya (1850-1891) was born into a noble Russian family and due to her gender had to overcome many obstacles in order to pursue her interest in mathematics. Barred from matriculating at Heidelberg, she audited lectures and later studied privately with Weierstrass, receiving a doctorate (in absentia) from Goettingen for an important paper on partial differential equations. Still, academic appointments eluded her. In 1884 she did obtain a position in Stockholm, thereafter winning honors and prizes, including the Prix Bordin in France.