/// <summary>
 ///   Date: 11/28/2011
 ///   Adds all sites which the transaction accessed if they are not in the list already.
 /// </summary>
 /// <param name = "t">The transaction to update.</param>
 /// <remarks>
 ///   Side effects: some sites may be added to the transaction's access list
 /// </remarks>
 private void AddSitesToAccessList(Transaction t)
 {
     // find all sites which returned a successful result for this transaction's last operation
     List<Result> accessedSites =
         results.FindAll(
             matching =>
             matching.IssuingTransaction == t.Id &&
             matching.Status == Enumerations.ResultStatus.Success);
     foreach (Result successResult in accessedSites)
     {
         t.AddAccessedSite(successResult.SiteNumber, successResult.TimeStamp);
     }
 }