P. Shearman, M. Sussex, European Security After 9/11(Ashgate, 2004) - According to Shearman and Sussex, both the UK and France were great powers now reduced to middle power status.
Flemes, Daniel, Emerging Middle Powers' Soft Balancing Strategy: State and Perspectives of the IBSA Dialogue Forum (ngày 1 tháng 8 năm 2007). GIGA Working Paper No. 57. doi:10.2139/ssrn.1007692
