@misc{misc6f4b6e40,
title   = {On the relevant systems P and P * and some related systems},
author = {Arruda, Ayda I. and Costa, Newton Carneiro Affonso da},
year = {1984},
doi = {10.1007/BF00935738},
publisher = {Springer Science},
journal   = {Studia Logica}
}