1. A.A. Abramov, N.B. Konyukhova, and K. Balla, Comput. Math. Banah Center Pubs., v. 13, 319–351 (1984) (in Russian).
2. A.A. Abramov, N.B. Konyukhova, SovJ. Numer. Anal. Math. Modelling, v. 1 (4), 245–265 (1986).
3. N.B. Konyukhova, Diff. Eq., v. 30 (8), 1284–1294 (1994).
4. N.B. Konyukhova, Comp. Maths Math. Phys., v. 34 (10), 1179–1195 (1994).
5. N.B. Konyukhova, Soobsch. po Prikl. Mat. VC RAN ( VC RAN, Moscow, 1996 ) (in Russian).