TY  - JOUR
AU  - Raina Ivanova
TI  - An Orthogonal Tangential Group of Transformations of a 4-Dimensional Riemannian Manifold
JO  - Mathematica balkanica
PY  - 1997
SP  - 57
VL  - 11
IS  - 1-2
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/MABA_1997_11_1-2_a6/
ID  - MABA_1997_11_1-2_a6
ER  -