TY  - JOUR
AU  - Hengartner, Walter
AU  - Szapiel, Wojciech
TI  - Extremal Problems for the Classes S R -p and T R -p
JO  - Canadian journal of mathematics
PY  - 1990
SP  - 619
EP  - 645
VL  - 42
IS  - 4
UR  - http://geodesic.mathdoc.fr/articles/10.4153/CJM-1990-033-x/
DO  - 10.4153/CJM-1990-033-x
ID  - 10_4153_CJM_1990_033_x
ER  -