著者名,論文名,雑誌名,ISSN,出版者名,出版日付,巻,号,ページ,URL,URL(DOI) LESTER J. C.,Lifelike pedagogical agents for mixed-initiative problem solving in constructivist learning environments,User Modeling and User-Adapted Interaction,,,1999,9,,1-44,https://cir.nii.ac.jp/crid/1571698601672858112,