Happy birthday to Russian #mathematician & writer Sofia Vasilyevna Kovalevski (1850-1891). Her contributions to analysis, differential equations & mechanics include Cauchy-Kovalevski theorem & the famed Kovalevski top. She was 1st woman appointed to full prof in N Europe or to serve as editor of a major sci journal. She is also remembered for her contributions to Russian literature. All of this despite living when women were still barred from attending university.