Michiko Kayashima Riichiro Mizoguchi A New Framework of Metacognition with Abstraction/Instantiation Operations. 362-364 2010 Intelligent Tutoring Systems (2) http://dx.doi.org/10.1007/978-3-642-13437-1_71 conf/its/2010-2 db/conf/its/its2010-2.html#KayashimaM10