@article {Risch96a,
author = {V. Risch},
title = {Analytic Tableaux for Default Logics},
journal = {Journal of Applied Non-Classical Logics},
volume = {6},
number = {1},
note = {special issue 1993 AAAI Fall Symposium on Automated Deduction in Non-Standard Logics},
year = {1996},
pages = {71--88}
}