Resource file(.resx) in Sub Application

Hi,
I'm converting an existing project from Website to Web Application.Everything else seems fine but I'm unable to access resources from parent application in sub application.
We use Resources.<Resource FileName>.<Resource Key> to access the resources in parent project. We have a class file as well to access resources, it internally uses HttpContext.GetGlobalResourceObject(). But we avoid using this class because Resources.<Resource FileName>.<Resource Key> syntax gives a build error if someone accidentally removes an existing resource, which I guess is not possible otherwise.All our resource files are under "App_GlobalResources" folder in the parent project.
Any help regarding accessing the resources from parent application in sub application is appriciated.
Thanks in advance.
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