Fig. 4

Network visualization map of country co-authorships. Legend: Countries with a minimum of 20 published articles were included. The map includes 32 countries in three clusters. Number of co-authorships was highest for the USA followed by South Africa and the UK. Strong collaborations were found between the following pairs of countries: USA – South Africa (link strength = 109), USA – Peru (link strength = 47), South Africa – UK (link strength = 42), USA – Switzerland (link strength = 42), USA – UK (link strength = 36), USA – Russian Federation (link strength = 30). USA – South Korea (link strength = 26), USA – China (link strength = 24), USA – Latvia (link strength = 25), and UK – Germany (link strength = 23)