Entropy measures of type-2 intuitionistic fuzzy sets and type-2 triangular intuitionistic trapezodial fuzzy sets
Zhensong Chen, Shenghua Xiong, Yanlai Li, and Kwai-Sang Chin
Journal of Systems Engineering and Electronics . 2015, (4): 774 .  DOI: 10.1109/JSEE.2015.00086