TY  - JOUR
AU  - P. G. Grinevich
AU  - S. P. Novikov
TI  - Real finite-zone solutions of the sine-Gordon equation: a~formula for the topological charge
JO  - Trudy Matematicheskogo Instituta imeni V.A. Steklova
PY  - 2001
SP  - 980
EP  - 981
VL  - 56
IS  - 5
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/RM_2001_56_5_a5/
LA  - en
ID  - RM_2001_56_5_a5
ER  -