Author,Title,Journal,ISSN,Publisher,Date,Volume,Number,Page,URL,URL(DOI) SHINDO Toshihiko and MAGARA Keiichi,Understanding “the Principle of Exchanging Variables” in a Formula of Intensive Quantity,THE JAPANESE JOURNAL OF PSYCHOLOGY IN TEACHING AND LEARNING,18800718,The Japanese Association of Psychology in Teaching and Learning,2014,10,1,12-24,https://cir.nii.ac.jp/crid/1390282681080179968,https://doi.org/10.20629/japtl.10.1_12