public void Publish(Quotation quotation)
 {
     if (quotation == null)
     {
         throw new ArgumentNullException(nameof(quotation));
     }
     if (Handler != null)
     {
         var clients = Handler.GetClients();
         var content = quotation.ToClient(false);
         clients.SendTextAsnyc(content, CancellationToken.None);
     }
 }