Figure 4 Author Co-citation Network. Figure A represents different researchers, with nodes representing them. The larger the node, the more frequently it is cited. The thickness and color of the inner circles of the nodes indicate the frequency of citations in different time periods. The lines between nodes represent the co-citation relationship, and their thickness indicates the strength of the co-citation. The color of the lines corresponds to the time of the first co-citation of the node, with the color changing from cool blue to warm red indicating the change of time from early to recent. Figure B, clustering analysis results are shown based on the LLS clustering method. Different color blocks represent different clusters. The position of the color blocks of the authors represented by different nodes indicates the corresponding research fields, with the color changing from cool blue to warm red indicating the change of time from early to recent.