internal override void WriteXML(XmlWriter writer)
{
writer.WriteStartElement("Type");
writer.WriteString(ItemType.GetItemTypeElementString());
writer.WriteEndElement();
writer.WriteStartElement("Position");
_position.WriteXML(writer);
writer.WriteEndElement();
writer.WriteStartElement("MajorAxis");
writer.WriteString(SemiAxis1.ToString());
writer.WriteEndElement();
writer.WriteStartElement("MinorAxis");
writer.WriteString(SemiAxis2.ToString());
writer.WriteEndElement();
}