Formation of an Association

We were owner of a plot of land which we developed into a multistoreyed building containing 6 flats and subsequently got possession. Our share in the building is 50% but rest 50% belongs to other ppl. Now at the time possession builder did not form an association stating it's not mandatory to form an association in a building containing 6 flats. After the possession we continued at our and shared the maintenance cost on arbitrary basis. I requested no of times the other ppl to sit and form an association which they refused to do. Now a situation has come where the building itself requires some maintenance and no one is interested in making any contribution My questions: 1. How can we form a legal association for the building even if the other members are not willing to join association formation meeting for the building 2. Post that what steps can we take to ensure that other members are legally responsible for paying the monthly maintenance fees of the building 3 What else legal steps I can take for smooth contribution flow from other members of the building