Authors: Geurt Essers; Sandra van Dulmen; Chris van Weel; Cees van der Vleuten; Anneke Kramer Journal: BMC Fam Pract Date: 2011-12-13 Impact factor: 2.497
Authors: S C Tonnon; K I Proper; H P van der Ploeg; M J Westerman; E Sijbesma; A J van der Beek Journal: BMC Public Health Date: 2014-12-23 Impact factor: 3.295