著者名,書名,版表示,出版者名,出版年,シリーズ名,番号,ISBN,ISSN,URL
"Siva Kumar, M. V. K.",Drought spells and drought frequencies in west Africa : Durée et fréquence des périodes sèches en Afrique de l'Ouest,,International Crops Research Institute for the Semi-arid Tropics,1991,Research bulletin (International Crops Research Institute for the Semi-arid Tropics),,9290661828,,https://cir.nii.ac.jp/crid/1130000795423647360