@article{PORMA_2001__58_4_50842,
     author = {Abad, M. and D{\'\i}az Varela, J. P. and Fern\'andez, A. and Meske, N. and Rueda, L.},
     title = {On cyclic symmetric {Heyting} algebras.},
     journal = {Portugaliae mathematica},
     pages = {389--406},
     publisher = {mathdoc},
     volume = {58},
     number = {4},
     year = {2001},
     zbl = {1042.06007},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/PORMA_2001__58_4_50842/}
}