TY  - JOUR
AU  - R. M. Geidel'man
TI  - Multidimensional ruled surfaces with holonomic families of $L^{\hat a}_s$-planes, and focal transforms of a~surface
JO  - Izvestiâ vysših učebnyh zavedenij. Matematika
PY  - 1975
SP  - 97
EP  - 100
IS  - 1
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/IVM_1975_1_a14/
LA  - ru
ID  - IVM_1975_1_a14
ER  -