Q. I've had to use the Interlibrary loan system at my college to access some of my journal articles ...

I would treat them as a print journal. More than likely that is the source they did come from.

To treat them as an online journal (i.e. from a website) would imply that you could (and should) supply a URL for access.

The beauty of ILL is that you don't have to worry about how things magically show up.  :)