1. Towards the many-body theory with the Galilei invariance as a guide, preceding article.
2. and , Variational Principles in Dynamics and Quantum Theory, Dover, New York, 1968.
3. See, for example, Classical Field Theory, John Wiley and Sons, New York, 1976;
4. An Invitation to A Galilei Invariant World, Festschrift in Honor of K. Nishijima, 1987.