MLA

Roussos, and George Roussos. Ubiquitous and Pervasive Commerce. Springer London, 2006.

APA

Roussos, R., & Roussos, G. (2006). Ubiquitous and Pervasive Commerce. Springer London.

Chicago

Roussos, and George Roussos. Ubiquitous and Pervasive Commerce. : Springer London, 2006.