@book{Crompvoets2006,
author = {Crompvoets, Joep},
booktitle = {PhD Thesis},
isbn = {9085043417},
language = {en},
pages = {136},
publisher = {Wageningen Universiteit},
shorttitle = {National spatial data clearinghouses},
title = {{National Spatial Data Clearinhouses Worldwide Development and Impact}},
year = {2006}
}