Marijana Gorjanac-Ranitovic Andreja Tepavcevic General form of lattice-valued fuzzy sets under the cutworthy approach. 1213-1216 2007 158 Fuzzy Sets and Systems 11 http://dx.doi.org/10.1016/j.fss.2006.12.016 db/journals/fss/fss158.html#Gorjanac-RanitovicT07