Aczel, J <br/><br/>
Functional Equations in Several Variables  With application to Mathematics, Information Theory and to the Natural and social Sciences 
by J Aczel and J Dhombres 
 - Cambridge  Cambridge University Press  2008 
 - xiii,462p 
 - Encyclopedia of Mathematics and its Applications No.31 .
<br/><br/><label>ISBN: </label>9780521063890 
<br/><br/><label>Dewey Class. No.: </label>515.84  / P08