Graded modalities. III (the completeness and compactness of S40). - Maurizio Fattorosi-Barnaba; Claudio Cerrato (Stud Logica, 1988)

General canonical models for graded normal logics (graded modalities IV). - Claudio Cerrato (Stud Logica, 1990)

Modal Sequents for Normal Modal Logics. - Claudio Cerrato (Math. Log. Q., 1993)

Cut-free modal sequents for normal modal logics. - Claudio Cerrato (Notre Dame J. Formal Log., 1993)

Natural Deduction Based upon Strict Implication for Normal Modal Logics. - Claudio Cerrato (Notre Dame J. Formal Log., 1994)

Decidability by Filtrations for graded normal logics (graded modalities V). - Claudio Cerrato (Stud Logica, 1994)

Modal Tree-Sequents. - Claudio Cerrato (Math. Log. Q., 1996)