Columbia University [Professor at a desk.]

Columbia University [Professor at a desk.]

Columbia University [Professor teaching a class.]

Columbia University [Professor teaching a class.]

Columbia University [Professor teaching a class.]

Columbia University [Professor teaching a class.]

Columbia University [Professor teaching a class.]

Columbia University [Professor teaching a class.]

Columbia University [Professor teaching a class.]

Columbia University [Professors talking in front of a chalkboard.]

Columbia University [Three professors talking in front of a chalkboard.]

Columbia University [Three professors talking in front of a chalkboard.]

Columbia University [Professor with students in an office.]

Columbia University [Professor with students in an office.]

Columbia University [Professor with students in an office.]

Columbia University [Professor with students in an office.]

Columbia University [Professor with students in an office.]

Columbia University [Students in a professor's office.]

Columbia University [Professor with students in an office.]

Columbia University [Sculpture professor.]