HUF property transfer through court

One of my family member dyed 40 years ago. His four sons (A, B, C, D) got a HUF residential plot through mutual partition agreement between brothers of their father in 1988. It means they all received the HUF property plot jointly. Mr A got a general power of attorney from B, C, and D in year 1978. Mr A with the help of this power of attorney with his wife and two sons, filed a family partition suit in 1996 in the civil court and got judgement in which they gave this property to the wife of Mr A. In the court case name of B, C, and D are mentioned but no remuneration or any part of this property or other property is given to B, C, and D in this partition. In 1998 Mr A and his family members (wife ,two sons and wives of two sons) filed another family partition suit in the civil court and gave this plot ( property} to younger son of Mr A. in this suit B,C and D not mentioned. In 2003 Mr A and his family members again filed a family partition suit in the civil court and now give this plot (property) to the wife of elder son of Mr A. In this suit B, C, and D not mentioned. Question- 1. Are these transfers of property legal when no stamp duty is paid and not registered in sub-registrar office? 2- Can a person use general power of attorney to transfer HUF property of his brothers to his own wife's or son's favor without given any remuneration to the property owners. 3- How can these orders be cancelled. 4-Any important Judgement of High Court or Supreme Court for reference.