Need advice on ownership of purchased land on father name in

My father was purchased a land in 1975 on my grand father name( just a name on registration papers. My father said that he was signed as buyer while doing the registration process but i found seller & witness names only in registered papers). I found one more registration document for the same survey no land on my father name. This was done in 1977( after 2 yrs). I thought that this might be for boundaries. In 1982, my father purchased one more land again on my grand father name only. My grandfather died in 1989/90. There was no will. He had 2 sons & 1 daughter. Till now we have been using these lands for cultivation. Land property tax was paid by my father with father name only. I have some of� those bills. Pattadar pass books are also there with my father & uncle names(� there is a mismatch in land area. Books shows, my father has� 18 cents where as my uncle has 36 cents for one of the mentioned land ) Please note this transaction was done before benami transaction prohibition act 1988. Can I claim my father as real owner of the mentioned lands. Now my uncle asking share in this?� please advice.