    @article {JoseA.Onieva2007a,
	title = {Integration of non-repudiation services in mobile DRM scenarios},
	journal = {Telecommunications Systems},
	volume = {35},
	year = {2007},
	month = {September},
	pages = {161-176},
	abstract = {<p>In any kind of electronic transaction, it is extremely important to assure that any of the parties involved can not deny their participation in the information exchange. This security property, which is called non-repudiation, becomes more important in Digital Rights Management (DRM) scenarios, where a consumer can freely access to certain contents but needs to obtain the proper Right Object (RO) from a vendor in order to process it. Any breach in this process could result on financial loss for any peer, thus it is necessary to provide a service that allows the creation of trusted evidence. Unfortunately, non-repudiation services has not been included so far in DRM specifications due to practical issues and the type of content distributed. In this paper we analyze how to allow the integration of non-repudiation services to a DRM framework, providing a set of protocols that allows the right objects acquisition to be undeniable, alongside with a proof-of-concept implementation and a validation process.</p>},
	keywords = {digital rights management, Mobile applications, Non-repudiation, Secure electronic commerce},
	issn = {1572-9451},
	author = {Jose A. Onieva and Javier Lopez and Rodrigo Roman and Jianying Zhou and Stefanos Gritzalis}
}
@inproceedings {Onieva2005,
	title = {Extending an OMA-based DRM Framework with Non-Repudiation Services},
	booktitle = {5th Symposium on Signal Processing and Information Technology (ISSPIT{\textquoteright}05)},
	year = {2005},
	pages = {472-477},
	publisher = {IEEE},
	organization = {IEEE},
	abstract = {<p>Digital Rights Management (DRM) is an umbrella term for any of several arrangements which allows a vendor of content in electronic form to control the material and restrict its usage in various ways that can be specified by the vendor. These arrangements are provided through security techniques, mainly encryption, and the distribution, in a detached manner, of content and rights. This allows free access to the content by the consumers, but only those carrying the proper Right Object (RO) will be able to process such content. As a security service considered in different layers of the security framework defined by ITU X.805, almost all applications need to consider non-repudiation in the very beginning of their design. Unfortunately this has not been done so far in DRM specifications due to practical issues and the type of content distributed. We analyze this service for the a DRM framework and provide a solution which allows the right objects acquisition to be undeniable.</p>},
	keywords = {digital rights management, Mobile applications, Non-repudiation, Secure electronic commerce},
	author = {Jose A. Onieva and Jianying Zhou and Javier Lopez and Rodrigo Roman}
}
