The set of catalogues where the service is being offered The set of services where this contract is part of The album the song belongs to The set of bids an actor has performed The set of services where the client is subscribed The set of content catalogues where the asset is being offered The signers of a contract: in this case a Content Provider and a Service Provider The set of Contracts a use case agent is involved in We assume only one address per use case agent The set of films directed by the person The set of songs and albums where the singer has participated The films an actor has participated in The actor who has made the bid The set of books or plots the person has written The date where the content was filmed, edited, ... Date where the content has been added to a catalogue to be offered The URI where the content is available true for male and false for female 0 9.8 30 15 0.384 CD-Compatible 30 25.0 30 25.0 9.8 25 MP3-Compatible 0.384 24