PAYMENT

Definition:	Monetary payment, without any further specification on the type, amount or purpose.
Label:	payment
Identifier:	payment.ttl
Note:	Such a constraint can be used to clarify whether a payment has been made or not.
Class:	Left Operand

Example:

"constraint": [{
	"leftOperand": "idsc:PAYMENT",
	"operator": "eq",
	"rightOperand": { "@value": "true", "@type": "xsd:boolean" }
}]