TY  - JOUR
AU  - N. T. Pham
TI  - Natural differential operators on manifolds, and boundary value problems that are elliptic in a subspace
JO  - Differencialʹnye uravneniâ
PY  - 1974
SP  - 1872
EP  - 1884
VL  - 10
IS  - 10
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DE_1974_10_10_a13/
LA  - ru
ID  - DE_1974_10_10_a13
ER  -