TY  - JOUR
AU  - Adams, Robert A.
TI  - -Δ is Positive Definite on a "Spiny Urchin"
JO  - Canadian mathematical bulletin
PY  - 1969
SP  - 229
EP  - 231
VL  - 12
IS  - 2
UR  - http://geodesic.mathdoc.fr/articles/10.4153/CMB-1969-028-7/
DO  - 10.4153/CMB-1969-028-7
ID  - 10_4153_CMB_1969_028_7
ER  -