What is the usual way to add an external assembly to ASP.NET MVC project?

I have an external compiled assembly with HtmlHelper extension methods. I need to use it in the project so that there wouldn't be any absolute references to this assembly because the project is shared with Team F开发者_如何转开发oundation Server. What is the usual way to solve the problem?

I usually have a lib folder that is part of the solution and which contains all third party assemblies used by the projects. As it is part of the solution it is version controlled by TFS. Also when you distribute the solution it will contain all the necessary references that are needed to build making it independent.