CList's AddTail() assertion error

CList's AddTail() assertion error

I was trying to create a double-dimensional List in MFC in order to save
and work with some int and CString data. So, I've tried something like
this:
#include "A.h"
//A.cpp
A::A()
{
}
A::~A()
{
}
//**********************
#pragma once
// A.h
class A: public CObject
{
public:
A();
virtual ~A();
int ID;
CString label;
};
//**********************
#include "A.h"
#pragma once
// B.h
class B : public CObject
{
public:
B();
virtual ~B();
int anotherID;
CString anotherLabel;
CList<A*, A*&> * AList;
CList<CString, CString&> * TestList;
};
//Note: B.cpp is pretty much the same as A.cpp
//*********************
//C.cpp
void C::Foo()
{
B * b = new B;
A * a = new A;
a->ID = 1;
a->label = L"something";
b->AList->AddTail(a); //Assertion error!
CString aux = L"another thing";
b->TestList->AddTail(aux); //Assertion error!
}
Here's the problem: when I try to use the AddList() method, I receive the
error "Access violation reading location". I first thought that the
problem was related to the CObject derived classes, but I am not sure if
this is the real problem. I've also tried to do some new and delete
overloading, but the problem became even worst. Any ideas?