The following typos exist in the ITEM_TABLE part of the Data Structures IM.
1. The instance structure example of ITEM_TABLE in Reference Model Data Structures specification needs to be updated due to removal of DV_QUANTITY_RATIO.
2. in the function ith_row(), the upper limit needs to inclusive to get the last row. The lower limit could be improved as "i >= 1" to be consistent with other invariants
i >0 and i < row_count