/// <see cref="IPortableObject"/>
void IPortableObject.WriteExternal(IPofWriter writer)
{
writer.WriteString(FIRST_NAME, m_firstName);
writer.WriteString(LAST_NAME, m_lastName);
writer.WriteObject(HOME_ADDRESS, m_addrHome);
writer.WriteObject(WORK_ADDRESS, m_addrWork);
writer.WriteDictionary(PHONE_NUMBERS, m_dictPhoneNumber,
typeof(string), typeof(PhoneNumber));
writer.WriteDate(BIRTH_DATE, m_dtBirth);
}