Columbia University [Man smoking.]
Columbia University [Unidentified man.]
Columbia University [Man speaking.]
Columbia University [Two men talking.]
Columbia University [Man in industrial space.]
Columbia University [Columbia University flag.]
Columbia University [Two men laughing.]
Columbia University [Group of men.]
Columbia University [Student studying.]
Columbia University [Mass examination.]
Columbia University [Man working with unidentified scientific equipment.]
Columbia University [Students talking.]