MathSciNet, the database of Mathematical Reviews, contains indexing and reviews back to 1940. Zentralblatt für Mathematik, a German publication, was the premier mathematics resource at the time, but the American Mathematical Society began publishing Mathematical Reviews in response to WWII and Zentralblatt's censorship of Jewish mathematicians. MathSciNet is preferred by American mathematicians while European mathematicians prefer ZBMath. The Jahrbuch is the German publication preceding Zentralblatt, and knowledge of the German language is necessary for use of the Jahbuch and for early years of publication for Zentralblatt. In recent decades, Zentralblatt has been published in English. The SPIN database will be useful for mathematical physics. Mathematical statistics is covered by MathSciNet.