1. de Freitas S (2008) Serious virtual worlds report. Joint Information Systems Committee, Bristol/London, UK
2. Messinger PR, Stroulia E, Lyons K (2008) A typology of virtual worlds: historical overview and future directions. J Virt Worlds Res 1(1):1–18
3. Sharma G, Qiang Y, Wenjun S, Qi L (2013) Communication in virtual world: second life and business opportunities. Inf Syst Front 15(4):677–694
4. Lukosch H, Van Nuland B, Van Ruijven T, Van Veen L, Verbraeck A (2014) Building a virtual world for team work improvement. In: 44th international simulation and gaming association conference (ISAGA). Springer, New York, pp 60–68
5. Surface EA, Dierdorff EC, Watson AM (2007) Special operations language training software measurement of effectiveness study: tactical Iraqi study final report. Special Operations Forces Language Office, Tampa, FL, USA