Gretzel, U., Höpken, W., Law, R., & Gretzel, U. Information and communication technologies in tourism 2009: Proceedings of the international conference in Amsterdam, the Netherlands, 2009 / [editors] Wolfram Höpken; Ulrike Gretzel; Rob Law. Springer-Verlag.
Trích dẫn kiểu ChicagoGretzel, Ulrikeeditors, Wolframeditors Höpken, Robeditors Law, và Ulrike editors Gretzel. Information and Communication Technologies in Tourism 2009: Proceedings of the International Conference in Amsterdam, the Netherlands, 2009 / [editors] Wolfram Höpken; Ulrike Gretzel; Rob Law. Springer-Verlag.
Trích dẫn MLAGretzel, Ulrikeeditors, Wolframeditors Höpken, Robeditors Law, và Ulrike editors Gretzel. Information and Communication Technologies in Tourism 2009: Proceedings of the International Conference in Amsterdam, the Netherlands, 2009 / [editors] Wolfram Höpken; Ulrike Gretzel; Rob Law. Springer-Verlag.