@inproceedings { IIIA-2007-1553, title = {Modal systems based on many-valued logics}, booktitle = {New dimensions in fuzzy logic and related technologies. Proceedings EUSFLAT 2007}, editor = {M. Stepnicka and V. Nov\'ak and U. Bodenhofer}, volume = {I}, year = {2007}, pages = {177-182}, abstract = {We propose a general semantic notion of modal many-valued logic. Then, we explore the difficulties to characterize this notation in a syntactic way and analyze the existing literature with respect to this framework.}, author = {F\`elix Bou and Francesc Esteva and Llu\'{\i}s Godo} }