Harvard college or harvard university?

i don't know how to address it in all my different letters for my app. which is it ive heard it both ways?

Harvard college or harvard university?
The institution is Harvard University. Universities have different colleges withing them such as college of business, college of nursing, college of arts and sciences etc. Within Harvard University is the undergraduate program which is called Harvard College. If you look at the admissions page you will see what I mean.......
Reply:Try "Harvard"