TY  - JOUR
AU  - W. Tonev
TI  - Positive definite functions on discrete commutative  semigroups.
JO  - Semigroup forum
PY  - 1979
SP  - 175
EP  - 184
VL  - 17
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/SF_1979__17_134316/
ID  - SF_1979__17_134316
ER  -