SOAP + PHP + WSDL

Some References :

1. http://www.scottnichol.com/nusoapprogwsdl.htm

2. http://www.ferdychristant.com/blog/articles/DOMM-6J2QFF

3. http://www.scottnichol.com/nusoapintro.htm

4. http://www.w3schools.com/soap/default.asp

5. http://developer.apple.com/internet/webservices/soapphp.html

6. http://www.vankouteren.eu/blog/2009/03/simple-php-soap-example/

Some Useful Software :

1. SoapUI

http://www.soapui.org/