3 articles have more than 50 co-authors and are therefore not shown.P. Speelman published from 2000 upto 2015 a total of 125 publications (at the UvA) with 50 or less co-authors. 236 unique co-authors in total with an average of 4.97 per article.The blue stripe (alt text: self) is the position of P. Speelman 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.