XML Commenting — How to properly mark a see also tag?

Question

I have the following and I'm not sure how to properly reference this in my XML commenting:

public static class FooExtensions
{
    public static Nullable<T> FooX<T>(this Nullable<T> foo) { ... }
}


public class Bar
{
    /// <summary>
    /// Bar Function
    /// </summary>
    /// <seealso cref="??"/>
    public void BarFunc() { ... }
}

So, my guess is <seealso cref="M:MyNamespace.FooExtensions.FooX{T}(this Nullable{T} foo)"/>, but I'm not 100% if that's correct. Does anyone know?

---

Oh, and I have the ECMA PDF document, but I still can't really figure it out even with that.