1. Transformation groups for soliton equations III;Date;J. Phys. Soc. Japan,1981
2. The n-component KP hierarchy and representation theory;Kac,1993
3. Universal Whitham hierarchy, dispersionless Hirota equations and multicomponent KP hierarchy;Takasaki;Phys. D,2007
4. The multicomponent KP hierarchy: differential Fay identities and Lax equations;Teo;J. Phys. A,2011
5. I. Krichever, A. Zabrodin, Quasi-periodic solutions of the universal hierarchy, arXiv:2308.12187.