@article{Toepoel2009,
author = {Toepoel, V. and Das, M. and Van Soest, A.},
title= {Design of web questionnaires: The effects of the number of items per screen},
year = {2009},
doi = {10.1177/1525822X08330261},
volume = {21},
number = {2},
pages = {200--213},
}