Only the current version so far — new entries appear as the app ships updates.
学研教室ライブラリー is a books & reference app by Gakken Inc. with 10,000+ downloads (about 22K estimated). +46 installs in the last 7 days. Install growth, rank history, SDKs and ad networks.
From the store listing: “This is a viewer for viewing Gakken e-books.”