no. 2
The arithmetic-geometric mean and isogenies for curves of higher genus
Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 4, Tome 28 (1999) no. 2, pp. 323-339. 
@article{ASNSP_1999_4_28_2_323_0,
     author = {Donagi, Ron and Livn\'e, Ron A.},
     title = {The arithmetic-geometric mean and isogenies for curves of higher genus},
     journal = {Annali della Scuola Normale Superiore di Pisa - Classe di Scienze},
     pages = {323--339},
     publisher = {Scuola normale superiore},
     volume = {Ser. 4, 28},
     number = {2},
     year = {1999},
     zbl = {0962.14021},
     mrnumber = {1736231},
     language = {en},
     url = {archive.numdam.org/item/ASNSP_1999_4_28_2_323_0/}
}
Donagi, Ron; Livné, Ron. The arithmetic-geometric mean and isogenies for curves of higher genus. Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 4, Tome 28 (1999) no. 2, pp. 323-339. http://archive.numdam.org/item/ASNSP_1999_4_28_2_323_0/

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