A note on the paper 'Combination of interval-valued fuzzy set and soft set' [Comput. Math. Appl. 58 (2009) 521-527]

摘要

1. Introduction Maji and Biswas [1] showed that the distributive law of soft sets is varied. But, Ali et al. [2] pointed out that it is not true in general. In this short article, we first provide a new concept which is a generalization of soft subset and soft equal. Using such notions, we consider the distributive law of soft sets. In the last year, Yang (the second author of this paper) et al. [3] established the distributive law of interval-valued fuzzy soft sets. The second aim of this paper is to point out it is not true, and then we consider more general notions than interval-valued fuzzy soft sets. Using the notions, we establish the distributive law, the so-called generalized distributive law, of interval-valued fuzzy soft sets.