References
- Bozer , Y.A. and White , J.A. ( 1984 ) Travel–time models for automated storage/reti ieval systems . HE Transactions 16 ( 4 ), 329 – 338 .
- Gudehus , T. ( 1973 ) Grundlagen der Kommissioniertechnik Dynamik der Waremerteilund Lagersysteme. [Principles of order picking operations in distribution and warehousing systems] , W. Girardet , Essen , West Germany .
- Hwang , H. and Lee , Seong B. ( 1990 ) Travel–time models considering the operating characteristics of the storage and retrieval machine . International Journal of Production Research 28 ( 10 ), 1779 – 1789 .