7Antepohl W, Domeij E, Forsberg P,et al. A follow-up of medical graduates of a problem-based learning curriculum [J]. Med Educ,2003,37(2) : 155-162.
8Do Imans DH, De Grave W, Wo Ljhagen LH, et al. Prob- lem-based learning: future challengas for educational Practice and research [J]. Med Educ,2005,39(5):732- 741.