How to add reference to assembly

Question

Hi:

I am currently developing in Visual Studio 2008 two solutions,the first is a web service project (WebService) and the second is a WCF project (WcfClient) where I will make call to the methods of the first one.
I added the Library reference of the first project to the second.

My problem is that when I made the call, it show me this error message:

Error 1 Type 'System.Web.Services.WebService "is defined in an assembly that is not referenced. You must add a reference to assembly 'System.Web.Services, Version = 2.0.0.0, Culture = neutral, PublicKeyToken = b03f5f7f11d50a3a. C: \ Documents and Settings \ Administrator \ My Documents \ Visual Studio 2008 \ Projects \ WcfLayer \ WcfClient \ client.c 18 13 WcfClient


Please heeeeeeeeeeeeeeeelp.     

knowing that i'm begginer.