Author,Title,Journal,ISSN,Publisher,Date,Volume,Number,Page,URL,URL(DOI) Iiguni Yoshiaki,Problems and Perspectives of Agriculture in Northeast Asia,Journal of Rural Problems,0388-8525,The Association for Regional Agricultural and Forestry Economics,2006,41,4,355-364,https://cir.nii.ac.jp/crid/1390282679466399872,https://doi.org/10.7310/arfe1965.41.355