@article{oai:klc.repo.nii.ac.jp:00000016,
 author = {Axton, Kevin},
 journal = {紀要visio : research reports, Visio},
 month = {Jul},
 pages = {23--42},
 title = {The Role of Portfolios in Student Motivation},
 volume = {42},
 year = {2012}
}