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 [Professor with students in an office.]

Columbia University [Student with professor in an office.]

Columbia University [Professor with students in an office.]

Columbia University [Professor with student in an office.]

Columbia University [Professor with students in an office.]

Columbia University [Students and professor in an office.]

Columbia University [Students and professor in an office.]

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

Columbia University [Students and professor in an office.]

Columbia University [Professor teaching a class.]

Columbia University [Professor teaching a class.]

Columbia University [Professor teaching a class.]

Columbia University [Professor talking with student.]

Columbia University [Professor with a student.]

Columbia University [Medical students attending a lecture.]