'Update the specified I{node} by replacing the I{multiref} references with
the contents of the referenced nodes and remove the I{href} attribute.
@param node: A node to update.
@type node: L{Element}
@return: The updated node
@rtype: L{Element}'

def update(self, node):

    self.replace_references(node)
    for c in node.children:
        self.update(c)
    return node
