Power of autorney given from usa

One lady working in USA has given power of autorney to her mother, for selling and develop the property belong to her and attend the court and legal maters. The power of autorney written on white paper and duly attested by notery in USA. Witness given by americans, there is no date on the pages and the signatory is available on the last page only. And the power of autorney is not attested by any Indian authorities. Based on the above powe of autorney, mother sold theland lelong to the daughter staying in USA. Suggest whether the sale is valid or not, and can she attend the court on behalf of her daughter and can give evidencebin the court. Regards, Subba reddy