TY  - JOUR
AU  - A. L. Verner
TI  - On the extrinsic geometry of elementary complete surfaces with nonpositive curvature.~II
JO  - Sbornik. Mathematics
PY  - 1968
SP  - 99
EP  - 123
VL  - 4
IS  - 1
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/SM_1968_4_1_a6/
LA  - en
ID  - SM_1968_4_1_a6
ER  -