1. B. B. Kadomtsev and V. I. Petviashvili, “On the stability of solitary waves in weakly dispersive media,” Sov. Phys. Dokl., 15, 539–541 (1970).
2. Y. Kodama, “KP solitons in shallow water,” J. Phys. A: Math. Theor., 43, 434004 (2010).
3. Y. Kodama and L. Williams, “KP solitons, total positivity, and cluster algebras,” Proc. Natl. Acad. Sci. USA, 108, 8984–8989 (2011); arXiv:1105.4170v1 [math.CO] (2011).
4. Y. Kodama and L. Williams, “The Deodhar decomposition for the Grassmannian and the regularity of KP solitons,” Adv. Math., 244, 979–1032 (2013).
5. M. Sato, “Soliton equations as dynamical systems on infinite dimensional Grassmann manifolds,” in: Random Systems and Dynamical Systems (RIMS Kôkyûroku, Vol. 439), Kyoto Univ., Kyoto (1981), pp. 30–46.