Author,Title,Journal,ISSN,Publisher,Date,Volume,Number,Page,URL,URL(DOI) Je-Young Choi,The Correlation Length and the Critical Exponent ν through the Simplified Cluster Variation Method and the Coherent Anomaly Method,Journal of the Physical Society of Japan,00319015,Tokyo : Physical Society of Japan,1997-01,66,1,5-7,https://cir.nii.ac.jp/crid/1521417755574945792,