2Vincent Morelli et al. , NATO Enlargement: Alba- nia, Croatia, and Possible Future Candidates, Congres- sional Research Service, 2009, p. 13 .21.22. 被引量:1
3Philip H. Gordon, James B. Steinberg, "NATO En- largement.. Moving Forward", Brookings Policy Brief, December 2001, No. 90, p. 1. 被引量:1