Test deployment failed for indirect reference assembly not found, Visual Studio 2008

I am new to unit testing. I was trying to run a simple unit test in Visual Studio 2008. The code I was testing uses a third party library. When I try to run the test, following error occurred.

"Warning: Test Run deployment issue: The assembly or module 'nuni开发者_StackOverflow社区t.framework' directly or indirectly referenced by the test container .... "

So I think, the library I am using has reference to nunit.framework. Should I install nunit or any better way to solve it?

Regards, Thanks.