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2. Chau, L.-L. and Lim, C.-S., Phys. Rev. Lett. 56, 294 (1986).
3. Chau, L.-L. and Milewski, B., “Light-Like Integrability and Supergravity Equations of Motion in D = 10, N = 1 Superspace”, UCD-87–05-R*; and Chau L.-L. and Lim, C.-S. to appear in Mod. Phys A. 1989.
4. Chau, L.L. and B. Milewski “Linear Systems and Conservation Laws in D=10, N=1 Supergravity”, to appear in Phys. Lett.
5. For general discussions on such equations, see, for example, G.L. Lamb, Jr., “Elements of Soliton Theory” (Wiley, New York, 1980);