|  Kalani, Amit and Priti Kalani. MCAD/MCSD Training Guide: Developing XML Web Services and Server Components with Microsoft Visual C# .NET and the Microsoft .NET Framework (Exam 70-320). Indianapolis, Indiana: Que Publishing, 2003.
Scribner, Kenn and Mark C. Stiver. Applied SOAP: Implementing .NET XML Web Services. Indianapolis, Indiana: Sams Publishing, 2001. Oellerman, William. Architecting Web Services. Berkeley, California: Apress, 2002.  Read the "Altering the SOAP Message Using SOAP Extensions" topic on MSDN at www.msdn.com/library/en-us/cpguide/html/cpconalteringsoapmessageusingsoapextensions.asp.
Read the "Accessing an XML Web Service Asynchronously in Managed Code" topic on MSDN at www.msdn.com/library/en-us/vbcon/html/vbtskCallingWebServiceAsynchronously.asp. Read the "Customizing SOAP Messages" topic on MSDN at www.msdn.com/library/en-us/cpguide/html/cpconcustomizingsoapinaspnetwebserviceswebserviceclients.asp. | 
