@inproceedings{inproceedings30524f00,
title   = {Chemical abundances of planetary nebulae towards the galactic anticenter},
author = {Costa, Roberto Dell'Aglio Dias da and Maciel, Walter Junqueira and Uchida, Monica M. M},
year = {2003},
publisher = {Astronomical Society of the Pacific},
booktitle   = {International Astronomical Union Symposium}
}