• Ownership

The case is as follows:
1. We are 3 children of our parents (2 brothers (married) 1 sister (adult and unmarried) 
2. In 1994 my father approached Mr Yadav who was allotted a plot of land through winning lottery conducted by GDA. At that time he was not in possession of plot. 
3. My father proposed to Mr Yadav that he would like to purchases his plot which was allotted to him by GDA. Mr.Yadav agreed. 
4. For this a bainama was signed on Rs 100 stamp paper and a token money of Rs.5000 was paid to him. In the bainama it was mentioned that Mr Yadav agree to sell and my father agree to purchase the plot for Rs 80,000 and that Rs 5000 is paid as advance and remaining Rs 75,000 would be paid at the time of registering sale deed.
5.On the appointed day my parents and Mr Yadav went to Ghaziabad Development Athority (GDA) and purchased the plot using general power of attorney given by Mr.Yadav to my mother. The sale deed was registered at sub registrar office. The said deed mentioned my Mother as PoA of Mr yadav as purchaser of the plot. It was signed by both GDA and my mother. A separate PoA was registered in sub-registrar office which mentioned my mother as PoA of Mr Yadav. The PoA gave all the authority to my mother to do whatever she wanted to do with this plot. It also mentioned that the hairs of Mr Yadav will have no objection in present and in future.
6. In 1995 my parents built a house and we all started living there and since then we all (3 of us with our family respectively) are living and occupying this plot and house built on it.
7. My mother died in 2004 leaving behind an unregistered will in the name of my father.
6. My father died in 2010 leaving behind a registered will in the name of us (equal estate to his 3 children)
7. In 2011 we went to GDA for mutation and they checked the sale deed and asked where in my mother (the PoA holder). We said she is no more. They said without her mutation can't be done and the plot now belongs to Mr Yadav. 
8. In 2012 we went to Court to take possession of plot. After 5 years of legal battle,waiting and spending lot of money, energy and time. The court ordered us to deposit current stamp duty of the land with it i.e court. We deposited the stamp duty in court and court drafted the sale deed and ordered Sub-Registrar to register the land in our name (i.e 3 of us). Thus we obtained the sale deed of the land in our name.
9. We took the sale deed to GDA to get the mutation done. But they (GDA authorities)are not co-operating and telling us that they will publish this matter in newspaper to invite objections from public and then wait for 1 month. If no objection come then they will initiate the process. 

Question: What is the exact process to be followed in this case to get mutation done in our name.