English interface: https://cir.nii.ac.jp/?lang=en

Japanese interface: https://cir.nii.ac.jp/?lang=ja

CiNii Research, provided by the National Institute of Informatics (NII), is a simple interface that allows users to cross-search not only books and journal articles but also research data from external collaborating institutions and institutional repositories. The list of databases incorporated in CiNii Research, see https://support.nii.ac.jp/en/cir/cir_db