title: Getting calendar's owner email address of an AppointmentItem
body: <p>I'm developing an Outlook Add-In to send all the appointments to a web app and I'm having some trouble consistently getting the "owner" (not the organizer) of an AppointmentItem.</p>
  
  <p>For example, X sends an appointment to Y and Z.
  The Add-In will get three appointment items out of it, I'm trying to get the email address of X, Y and Z.</p>
  
  <p>I tried to look into the SendUsingAccount (sometimes set to null) or the Parent property but I can't seem to find what I'm looking for.</p>
  
  <p>Thanks for your help!</p>