Dear Mr Sehgal,
If the property is self acquired by your father by his own earnings only then the Gift deed made by him in your favour is valid Please note.
In case the property is ancestral one he only can gift you his portion of that property as this will have undisputed shares of your sisters also.And only after taking a relinquishment deed from other share holders of the property it can be transferred in your name through a family settlement deed.
For further legal assistance on nominal charges, you can contact me on below mentioned address and Phone number, Please call after Court Hrs to get a suitable appointment date and timeing.
Advise, always take assistance from an experienced and well educated Advocate of the field. You can see my credentials on this very site for my appraisal.
Anand Bali & Associates
204-B Nanda Devi Apats
Plot-19, Sec-10.
Dwarka, New Delhi-75
(Near Dwarka Sec-11 Metro St.)
Ph: 09582144748