  Based on the citation data of journals covered by the China Scientific and
Technical Papers and Citations Database (CSTPCD), we obtained aggregated
journal-journal citation environments by applying routines developed
specifically for this purpose. Local citation impact of journals is defined as
the share of the total citations in a local citation environment, which is
expressed as a ratio and can be visualized by the size of the nodes. The
vertical size of the nodes varies proportionally to a journal's total citation
share, while the horizontal size of the nodes is used to provide citation
information after correction for the within-journal (self-) citations. In this
study, we analyze citation impacts of three Chinese journals in mathematics and
compare local citation impacts with impact factors. Local citation impacts
reflect a journal's status and function better than (global) impact factors. We
also found that authors in Chinese journals prefer international instead of
domestic ones as sources for their citations.
