private XmlNode PreviousSiblingTail(XmlNode node, XmlNode sibling) {
while (sibling == null) {
node = node.ParentNode;
if (node == null
|| node.NodeType != XmlNodeType.EntityReference) {
return null;
}
sibling = node.PreviousSibling;
}
while (sibling != null
&& sibling.NodeType == XmlNodeType.EntityReference) {
sibling = sibling.LastChild;
}
return sibling;
}