@article{BUMI_2006_8_9B_3_a10,
     author = {Rosales, J. C.},
     title = {Adding or removing an element from a pseudo-symmetric numerical semigroup},
     journal = {Bollettino della Unione matematica italiana},
     pages = {681--696},
     year = {2006},
     volume = {Ser. 8, 9B},
     number = {3},
     zbl = {1147.20052},
     mrnumber = {MR2274120},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/BUMI_2006_8_9B_3_a10/}
}