|
|
|
|
References
|
|
| |
| 1. |
S. Saito, N. Saitoh, Phys. Lett. A, 123 (1987), 283    |
| 2. |
J. Weiss, Phys. Lett. A, 137 (1989), 365 |
| 3. |
N. Kamran, K. Tenenblat, Duke Math. J., 84 (1996), 237  |
| 4. |
E. V. Ferapontov, TMF, 110:1 (1997), 86  |
| 5. |
C. Athorne, Phys. Lett. A, 206 (1995), 162 |
| 6. |
C. Athorne, Inverse Problems, 9 (1993), 217 |
| 7. |
C. Athorne, J. Phys. A, 31 (1998), 6605 |
| 8. |
C. Athorne, J. J. C. Nimmo, Inverse Problems, 7 (1991), 645 |
| 9. |
J. C. McConnell, J. C. Robson, J. Algebra, 26 (1973), 319 |
| 10. |
H. P. Rehm, J. Reine Agnew. Math., 307:8 (1979), 1 |
| 11. |
S. C. Coutinho, A primer of algebraic $D$-modules, CUP, Cambridge, 1995 |
| 12. |
A. J. Majid, Lectures on differential Galois theory, Amer. Math. Soc., New York, 1994 |
