Manuel Ojeda-Aciego Gerhard Brewka Inman P. de Guzmán Luís Moniz Pereira Preface. 3-5 2002 72 Studia Logica 1 db/journals/sLogica/sLogica72.html#Ojeda-AciegoBGP02 http://dx.doi.org/10.1023/A:1020534210459