A photo caption on page 15 of the Friday, May 7 issue incorrectly stated that the John Hancock Tower in Boston was designed by I.M. Pei ’40. While the Tower was designed by Pei’s firm, Pei Cobb Freed and Partners, the architects were Henry N. Cobb and Harold Fredenburgh, not Pei.

An article on Friday, May 11, about the Physics Rock Concert gave the wrong year for Yelena S. Bagdasarova, who graduates today. She is in the class of 2010, not the class of 2011.