SELECT Personen.lfdNrP, Personen.Anrede, Personen.Name, Personen.Vorname 
FROM Personen
WHERE Personen.lfdNrP NOT IN 
   (SELECT Personen.lfdNrP 
   FROM Personen, PzuR, Reisen
   WHERE Personen.lfdNrP = PzuR.lfdNrP
          AND PzuR.lfdNrR = Reisen.LfdNrR
          AND (Reisen.LfdNrR = " & DS & "))
   ORDER BY Personen.Name"