TY  - JOUR
AU  - M. Sharir
AU  - D. Halperin
TI  - New Bounds for Lower Envelopes in Three Dimensions, with Applications to Visibility in Terrains.
JO  - Discrete & computational geometry
PY  - 1994
SP  - 313
EP  - 326
VL  - 12
IS  - 1
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DCG_1994__12_1_131334/
ID  - DCG_1994__12_1_131334
ER  -