Delfino Codazzi (March 7, 1824 - July 21, 1873) was an Italian mathematician. He made some important contributions to the differential geometry of surfaces, e.g. Codazzi equation also known as the Mainardi-Codazzi equation. March 7 is the 66th day of the year in the Gregorian Calendar (67th in Leap years). ... 1824 was a leap year starting on Thursday (see link for calendar). ... July 21 is the 202nd day (203rd in leap years) of the year in the Gregorian Calendar, with 163 days remaining. ... 1873 was a common year starting on Wednesday (see link for calendar). ... A mathematician is a person whose area of study and research is mathematics. ... In mathematics, differential topology is the field dealing with differentiable functions on differentiable manifolds. ...