To cite the WWGbook package in publications use:
West, B., Welch, K. & Galecki, A. (2006) Linear Mixed Models: A Practical Guide Using Statistical Software. First Edition. Chapman Hall / CRC Press. ISBN 1584884800
Corresponding BibTeX entry:
@Book{, title = {Linear Mixed Models: A Practical Guide Using Statistical Software}, author = {B. West and K. Welch and A. Galecki}, publisher = {Chapman Hall / CRC Press}, edition = {First}, year = {2006}, note = {ISBN 1584884800}, url = {http://www-personal.umich.edu/~bwest/almmussp.html}, }