Fig. 10
From: Networks of international football: communities, evolution and globalization of the game
Adjacency matrices and visualization for decade 1901-1910 and 1931-1940. Left: adjacency matrices. Right: network visualization. In (b) and (d), each color stands for one community. In early decades, boundaries between communities in the adjacency matrices as shown in (a) and (c) were not clear, and the correspondence between community assignment and confederation as shown in (b) and (d) was poor