@article{10_21136_AM_1982_103980,
     author = {Spal, Jind\v{r}ich},
     title = {Fundamentals of a mathematical theory of fuzzy sets},
     journal = {Applications of Mathematics},
     pages = {326--340},
     publisher = {mathdoc},
     volume = {27},
     number = {5},
     year = {1982},
     doi = {10.21136/AM.1982.103980},
     mrnumber = {0674979},
     zbl = {0505.94033},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/AM.1982.103980/}
}