@article{article8c520730,
title   = {Regression models for pretest/posttest data in blocks},
author = {Singer, Júlio da Motta and Nobre, Juvêncio Santos and Sef, Henry Corazza},
year = {2004},
doi = {10.1191/1471082X04st083oa},
journal   = {Statistical Modelling}
}