5MOED H F. Measuring China: research performance using the Science Citation Index [J]. Scientometrics, 2002, 53 (3): 281 -296.
6LAW J, BAUIN S, COURTIAL J P , et al. Policy and the mapping of scientific change : a co - word anal ysis of research into environmental acidification [J]. Scientometrics, 1988, 14 (3-4): 251-264.