Butler, Graham (Aarhus University, Denmark),Wessel, Professor Ramses A (University of Groningen, the Netherlands)
（1）
Ramses A Wessel (University of Groningen),Joris Larik (Leiden University)
（1）
Santos Vara, Juan (University of Salamanca, Spain),Wessel, Ramses A. (University of Groningen, Netherlands)
（1）
；Butler, Graham (University of Southern Denmark),Wessel, Professor Ramses A (University of Groningen, the Netherlands)
（1）
