@article{SEMR_2006_3_a30,
     author = {R. R. Isangulov},
     title = {Isospectral flat orientable $2$-orbifolds},
     journal = {Sibirskie \`elektronnye matemati\v{c}eskie izvesti\^a},
     pages = {60--61},
     publisher = {mathdoc},
     volume = {3},
     year = {2006},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SEMR_2006_3_a30/}
}