Difference in book value data

I am current doing market research on reliance industries. While reading the annual report and comparing the data to the financial data of the company on MORNING STAR website I found huge differences in the book values over the years. Moreover, on doing my own calculation I found my value to be different too, however my calculations were closer to that of the data on morning star. Can you please explain the discrepancy ?

@Karthik @Risk.Money