How to get ownership of a joint property in which i am living for last 35 yrs.

Hello Sir, I am staying in Kolkata for last 35 years in a property build by my father and has all our brothers name in the property deed. The other two properties in Jorhat, Assam has my parents name on it and are currently occupied by my brothers (one each). Both my parents are dead now and without a proper "will" all three of us (brothers) are now in disagreement. Both my brothers are now claiming that the need their portion in Kolkata property in which i am currently living, they are threatening and harassing us mentally very often. I tried to negotiate saying that i won't claim the other two properties in Jorhat, Assam but i won't give anything from Kolkata property as i am living here for last 35 yrs. I have paid a portion of money to my father while buying this land and building this 2 storied house and is paying taxes and other maintenance costs since then. I have a sister too and is happily married, she claimed that she is not interested in any of the properties that our father owned and is ready to give up her portion to me as a gift. Seeing my unique scenario, what are my options ? 1) can i file a case in court claiming that since i am living in this property for last 35 yrs and is paying all taxes and bearing all the maintenance cost, i should be the rightful owner of this property and not my brothers even though the name is present in the property deed. 2) what happens if they file a court case against me claiming they need their portion in Kolkata property. how can i defend myself. 3) Any other way to solve the problem, since negotiation is not working out so far? Thanks & Regards, shomeprasanjit