Plank, Frans. 2009. WALS values evaluated. Linguistic Typology 13. 41-75.
@article{jacquesestimative-plank09wals,
author = {Plank, Frans},
journal = {Linguistic Typology},
pages = {41-75},
title = {WALS values evaluated},
volume = {13},
year = {2009}
}