Figure 3.

Collaborating countries for IgY-related research. Nodes in the network represent countries. Node size: the amount of publications of the country; node color: the time of publication of the literature, from the center of the node to all around, color from green to yellow, time from 1980 to 2021; purple circle: institutional centrality (intermediary centrality of the node where the purple circle appears ≥ 0.1); line: the diameter represents the degree of international cooperation, color from purple to yellow represents the time from 1980 to 2021.