*3.3. Countries*

The included articles were published in 22 countries (see Figure 7). India stands out with a third of all publications: 20 published articles. Worthy of mention is the fact that the African continent only provided 7 articles (slightly above 10%), and 2 of those were published in Mauritius, an eastern African archipelago with a population of less than a million and a half. On the other hand, the Asian continent shows a contribution close to 47% with 28 articles. The second most expressive value is not a country but scientific multinational collaboration; with 10 published articles, it represents about 17% of the total. From the total of 9 published articles on the European continent, a third were published in Portugal.

**Figure 7.** Countries of origin. Source: WoS and Scopus (27 January 2021).
