Helberger, N. (2005). Controlling access to content: Regulating conditional access in digital broadcasting. Kluwer law international.
Dyfyniad Arddull ChicagoHelberger, Natali. Controlling Access to Content: Regulating Conditional Access in Digital Broadcasting. Netherlands: Kluwer law international, 2005.
Dyfyniad MLAHelberger, Natali. Controlling Access to Content: Regulating Conditional Access in Digital Broadcasting. Kluwer law international, 2005.
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