TY  - ELEC
A1  - Bates, D.
A1  - Maechler, M.
A1  - Bolker, B. 
T1  - lme4: Linear mixed-effects models using S4 classes, 2011. R package version 0.999375-42
Y1  - 2012
UR  - http://CRAN.Rproject.org/package=lme4

ER  -