@book {4452, title = {Handbook of Mathematical Fuzzy Logic - volume 2}, series = {Studies in Logic, Mathematical Logic and Foundations}, number = {38}, year = {2011}, pages = {474}, publisher = {College Publications}, organization = {College Publications}, edition = {Petr Cintula, Petr H{\'a}jek, Carles Noguera}, address = {London}, isbn = {978-1-84890-054-7}, author = {Petr Cintula and Petr H{\'a}jek and Carles Noguera}, editor = {S. Artemov and S. Buss and D. Gabbay and S. Shelah and J. Siekmann and J. van Benthem} }