private string WriteWorker(XmlWriter writer, Person person)
{
var workerId = person.Id.FindIsoId() ?? GenerateId();
TaskWriter.Ids.Add(workerId, person.Id);
writer.WriteStartElement(XmlPrefix);
writer.WriteAttributeString("A", workerId);
writer.WriteAttributeString("B", person.LastName);
writer.WriteXmlAttribute("C", person.FirstName);
var contactInfo = FindContactInfo(person.ContactInfoId);
WriteContactInfo(writer, contactInfo);
writer.WriteEndElement();
return workerId;
}