(self.slot->select(sl : SlotType1 | (not sl.name.oclIsUndefined()) and (sl.name = 'serviceStopTime'))->size() < 2) and 
self.slot->select(sl : SlotType1 | (not sl.name.oclIsUndefined()) and (sl.name = 'serviceStopTime'))->forAll(sl : SlotType1 | 
	(not sl.valueList.oclIsUndefined()) and (sl.valueList.value->size()=1) 
)