Restore address book from OST

I’ve a question, I’ve a friend who needs to import her data from Outlook for windows into OL 2011 on Mac. I though the best way to do it was copy her data directory. when i tried to recover her address book on the OL on Mac, I see that all I backup was OST files and no PST. Is it possible to recover her address book from the OST? I had google this extensively and no official answers been found that is same as what her situation is.