public function getFirstOperation()
    {
        $returnValue = null;

        
        if(empty($this->firstOperation)){
        	$property = new core_kernel_classes_Property(RulesRdf::PROPERTY_OPERATION_FIRST_OP);
        	$resource = $this->getUniquePropertyValue($property);
        	$this->firstOperation = new core_kernel_rules_Term($resource->getUri());
        }
        $returnValue = $this->firstOperation;
        

        return $returnValue;
    }