mathematic book?
personally, i learned fourier series and laplace transform thru a mathematics text book named ;
Book - Advanced Engineering Mathematics, 2nd Ed., 2000
Author - Zill, D.G. and Cullen, M.R
But then i'm using 2 more engineering approach reference books that discuss mistly about Z-transform, Fourier Series, Laplace Transform
1) Introduction To Signals n Systems 2nd edition
Author - Edward W.Kamen
Publisher - Maxwell Macmillan Int. Edition
2) Continuous n Discrete Signals n Systems 2nd edition
Author - Samir S.Soliman, Mandyam D.Srinath
Publisher - Prentice Hall