public function isDRSValidForFact( $fact,  $drs)
	{
		foreach ( $drs as $hypercube => $roles )
		{
			foreach ( $roles as $role => $hypercubeItems )
			{
				if ( ! isset( $hypercubes[ $hypercube ][ $role ] ) )
				{
					$closed = isset( $hypercubeItems['parents'][ $fact['label'] ]['closed'] ) && $hypercubeItems['parents'][ $fact['label'] ]['closed'];

					if ( ! $this->isHypercubeDimensionallyValid( $fact['contextRef'], $hypercubeItems, $closed ) ) continue;

					return true;
				}
			}
		}

		return false;
	}