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
"Northrup, David",Trade without rulers : pre-colonial economic development in South-Eastern Nigeria,,Clarendon Press,1978,Oxford studies in African affairs,,0198227124,,https://cir.nii.ac.jp/crid/1130282268809738624