@article{article5f6f6648,
title   = {Definitions: the primitive concept of logics or the Leśniewski–Tarski legacy},
author = {López-Escobar, Edgar George Kenneth and Miraglia Neto, Francisco},
year = {2002},
doi = {10.4064/dm401-0-1},
journal   = {Dissertationes Mathematicae}
}