Figure 2From: Trends in scientific activity addressing transmissible spongiform encephalopathies: a bibliometric study covering the period 1973–2002 Author's clusters and their position in the research subjects-matters space, 1983–1992. Circles represent author's clusters, and their size show the cluster's productivity. They are placed next to their main subjects of research. The asterisks show the subject matters, related to the angle and proximity to axis.Back to article page