Where to extract data from Master mtr div?

In a DIV if I right click, in "Managed Division", "Traces", "View Marks", it shows up Master mtr div file with Mark and Session info. I can see there are *mtr_div.sde files. If I "cat" those files I can see the "Marks" info but no session numbers there. My question is where and how we can extract mark and session div data. Appreciate if anyone can help me on this? Many thanks in advance. Kwan