1. Innovation and Productivity Growth in the EU Services Sector; European Investment Bank: Luxembourghttp://www.eib.org/attachments/efs/efs_innovation_and_productivity_en.pdf
2. Global business services
3. A Handbook of International Trade in Services;Mattoo,2008
4. ICTSD Policy Paper on Trade in Services and Sustainable Developmenthttps://www.ictsd.org/downloads/2008/06/gallagher.pdf
5. World Trade in Services: Evidence from a New Dataset;Loungani,2017