BibTex format
@article{Conradie:2009:10.1080/03031853.2009.9523814,
author = {Conradie, B and Piesse, J and Thirtle, C},
doi = {10.1080/03031853.2009.9523814},
journal = {AGREKON},
pages = {9--20},
title = {What is the appropriate level of aggregation for productivity indices? Comparing district, regional and national measures},
url = {http://dx.doi.org/10.1080/03031853.2009.9523814},
volume = {48},
year = {2009}
}