Select NomEmplacement
From Emplacements
Where IdEmplacement In (
Select IdEmplacement
From Emplacements
Where reftype=3
Except
Select Distinct Idemplacement
From sEjours INNER JOIN Emplacements ON IdEmplacement = RefEmplacement
Where (Reftype=3 AND ((DateDebut <= 'May 20,2007' AND DateFin<= 'June 3,2007') OR 
(DateDebut<= 'june 3 , 2007' And DateFin >= 'june 3 , 2007') OR 
(DateDebut<= 'May 20 , 2007' And DateFin >= 'May 20 , 2007'))));