TY  - BOOK
AU  - Lecture given at a summerschool at Erice/Sicily, 1974
AU  - Hanken,H.,ed.
TI  - Cooperative effects: progress in synergetics
SN  - 072040309X
U1  - 530 
PY  - 1974///
CY  - Amsterdam
PB  - North-Holland Publishing Company
ER  -