و عليكم السلام و رحمة الله
هذه كتب الموضوع الذي طلبتيه أرجو أن يفيدك
Linear Partial Differential Equations for Scientists and Engineers
par: Tyn Myint-U, Lokenath Debnath
RARed PDF / 4.6MB
password: twilightzone
http://rapidshare.com/files/72378488/ebc_oovlg5mk.rar

Nonlinear Partial Differential Equations for Scientists and Engineers
par: Lokenath Debnath
DJVU / 3.9 MB
http://rapidshare.com/files/4205394/..._Engineers.rar

Partial Differential Equations for Scientists and Engineers
par: Geoffrey Stephenson
djvu / 2.7MB
http://rapidshare.com/files/11401522...henson_PDE.rar

Elements of Partial Differential Equations
par: Ian N. Sneddon
PDF / 70MB
http://rapidshare.com/files/82035057...-Dover2006.rar