Multi-quasielliptic polynomials
Annali della Scuola Normale Superiore di Pisa - Scienze Fisiche e Matematiche, Série 3, Tome 21 (1967) no. 2, pp. 239-260. 
@article{ASNSP_1967_3_21_2_239_0,
     author = {Friberg, J\"oran},
     title = {Multi-quasielliptic polynomials},
     journal = {Annali della Scuola Normale Superiore di Pisa - Scienze Fisiche e Matematiche},
     pages = {239--260},
     publisher = {Scuola normale superiore},
     volume = {Ser. 3, 21},
     number = {2},
     year = {1967},
     mrnumber = {221090},
     zbl = {0161.07803},
     language = {en},
     url = {http://archive.numdam.org/item/ASNSP_1967_3_21_2_239_0/}
}
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Friberg, Jöran. Multi-quasielliptic polynomials. Annali della Scuola Normale Superiore di Pisa - Scienze Fisiche e Matematiche, Série 3, Tome 21 (1967) no. 2, pp. 239-260. http://archive.numdam.org/item/ASNSP_1967_3_21_2_239_0/

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