An Introduction to Modern Japanese and Cambridge Intermediate Japanese

Not sure if this has been shared here before, but official digitized copies of both of these textbooks are available online.

Introduction to Modern Japanese (including answer key): https://www.ames.cam.ac.uk/subjects/japanese-studies/introduction-modern-japanese

Cambridge Intermediate Japanese: https://www.ames.cam.ac.uk/subjects/japanese-studies/cambridge-intermediate-japanese