you can use the old BKINA.run menu, or the T6INA.run menu just by fixing your menu access in TAS-G.
 
or, if you continue to use the new windows version T7INA.rwn then you will want to modify the Drill down grid for Inventory Transactions.
 
to do so, you would use SU-A lookup the INVTRANS grid, add another line that will then have and display the field MTIT.REF  
 
hth