Passing variables by reference

Hello, I have a quick question regarding passing variables by reference that reside within a class. On most tutorials that I've seen (I dunno, actually I haven't seen this covered at all really) they simple have the a private class variable and a public function which takes the variable to modify it. What I'm saying might be hard to picture, so here's an example (of exactly what I'm trying to do!):

http://www.relisoft.com/win32/winnie.html

Code:

class WinClass
{
public:
    WinClass (WNDPROC winProc, char const * className, HINSTANCE hInst);
    void Register ()
    {
        ::RegisterClass (&_class);
    }
private:
    WNDCLASS _class;
};

I was wondering if, instead, I could do something like this:

Code:

class SomeClass {
public:
     WNDCLASS _wndClass
}

...somemorecodehere...

SomeClass* someClass = new SomeClass;
::RegisterClass(& (someClass->_wndClass) );

Naturally, this doesn't work, I do not know exactly what it is resolving the address of, but it's not passing my wndClass by reference to the function (I don't think!). If this really is the method I should use, I don't know my problem is and I'll post more of my code...or if this is completely not allowed in C++, sorry for being stupid . Thanks for your time

Tonto