A supply of services may consist, inter alia, in one of the following transactions:

1. (a)

   the assignment of intangible property, whether or not the subject of a document establishing title;

2. (b)

   the obligation to refrain from an act, or to tolerate an act or situation;

3. (c)

   the performance of services in pursuance of an order made by or in the name of a public authority or in pursuance of the law.