TY  - JOUR 
T1  - Analysis and models of operators activities in complex natural life environments
JO  - Production
A1  - Montmollin, Maurice de
SN  - 0103-6513
UL  - 10.1590/S0103-65131999000400002
VL  - 9 
Y1  - 1999
PB  - Brasil 
ER  -