Csc.exe refers to an external .dll file

I am trying to create a simple program c#using Growl C# API.

I tried to compile my program in two ways:

1) I saved the file .dllin the same directory as my file .cs. Than I ran

csc /r:Growl.Connector.dll,Growl.CoreLibrary.dll /out:test.exe *.cs

It compiled and works great.

2) Now I created a directory in my current working directory with the name growland saved all mine there .dll.

Now when I try to compile it using the following command

csc /r:"D:\Modified\Growl_NET_Connector_SDK\libraries\growl\Growl.Connector.dll","D:
\Modified\Growl_NET_Connector_SDK\libraries\growl\Growl.CoreLibrary.dll" /out:test.exe *.cs

It compiled fine, but when I tried to run it, the following exception occurred.

Unhandled Exception: System.IO.FileNotFoundException: Could not load file or assembly 'Growl.Connector, Version=2.0.0.0, Culture=n
eutral, PublicKeyToken=980c2339411be384' or one of its dependencies. The system cannot find the file specified.
 at GrowlNotification.Program.Main(String[] args)

So my question is the correct way to link to a .dllfile in cscwhen the files are in an external folder.

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