@InProceedings{LibeRighSala09,
author = {Federico Liberatore and G. Righini and Matteo Salani },
title = {A pricing algorithm for the vehicle routing problem with soft time windows},
booktitle = {Innovations in Distribution Logistics},
pages = {251-266},
editor = {L. Bertazzi, M.G. Speranza, J. Nunen},
volume = {619},
series = {LNEMS},
publisher = {Springer},
note = {ISBN:978-3-540-92943-7},
year = {2009}
}