Finding First Item In Subset

I have a list that kind of looks like this. I sorted it by date, then by location, and then by time. I need to find the earliest item in one location on a given day and display as a list.

datelocationtime
6/1/2013 A730
6/1/2013 A745
6/1/2013 A750
6/1/2013 B800
6/1/2013 B810
6/1/2013 C730
6/1/2013 C745
6/1/2013 C800
6/1/2013 C815
6/2/2013 A730
6/2/2013 A745
6/2/2013 A800
6/2/2013 A815
6/2/2013 B700
6/2/2013 B800
6/2/2013 B815
6/2/2013 C800
6/2/2013 C815