read it in "Number Theory in Progress" book , otherwise read attached links papers also

http://arxiv.org/pdf/1202.5785.pdf

Dear Zulqumain,  

First thank you very much for your help.

Please I will be thankful if you send the first reference in attached file, because I can't open it ( it shows me a message saying: you can't connect to this link because it is not safety ).

The second article is not about Pisot-Dufresnoy-Boyd Algorithm.

Dear Hanifa

This paper presents two algorithms on certain computations

about Pisot numbers

https://arxiv.org/pdf/1202.5785.pdf