4 articles have more than 50 co-authors and are therefore not shown.W.J. Buma published from 2000 upto 2015 a total of 97 publications (at the UvA) with 50 or less co-authors. 265 unique co-authors in total with an average of 5.07 per article.The blue stripe (alt text: self) is the position of W.J. Buma in the write position for the article. Every row is an unique article. The amount of credits for a certain Author position, also called write position, does differ by discipline. Some journals publish author names in alphabetical order. This is common practice by publications with many authors.