@inbook{Langford2001,
author = {Langford, I.H. and Day, R.J.},
title= {Poisson Regression},
year = {2001},
editor = {Leyland, A.H.},
editor = {Goldstein, H.},
booktitle = {Multilevel Modelling of Health Statistics},
address = {Chichester},
publisher = {John Wiley & Sons LTD},
pages = {45--57},
}