@ARTICLE {2918,
author={L. Cruz-Filipe and A. Sernadas and C. Sernadas},
doi={10.1093/jigpal/jzm057},
journal={Logic Journal of the IGPL},
title={Heterogeneous fibring of deductive systems via abstract proof systems},
year={2008},
month={January},
volume={16},
number={-},
pages={121-153},
ISSN={1367-0751}
}