The period function near a polycycle with two semi-hyperbolic vertices
Annales Mathématiques Blaise Pascal, Tome 8 (2001) no. 1, pp. 93-104.
@article{AMBP_2001__8_1_93_0,
     author = {Mansilla, Ang\'elica and Saavedra, Mariana},
     title = {The period function near a polycycle with two semi-hyperbolic vertices},
     journal = {Annales Math\'ematiques Blaise Pascal},
     pages = {93--104},
     publisher = {Laboratoires de Math\'ematiques Pures et Appliqu\'ees de l'Universit\'e Blaise Pascal},
     volume = {8},
     number = {1},
     year = {2001},
     zbl = {01690886},
     mrnumber = {1863649},
     language = {en},
     url = {www.numdam.org/item/AMBP_2001__8_1_93_0/}
}
Mansilla, Angélica; Saavedra, Mariana. The period function near a polycycle with two semi-hyperbolic vertices. Annales Mathématiques Blaise Pascal, Tome 8 (2001) no. 1, pp. 93-104. http://www.numdam.org/item/AMBP_2001__8_1_93_0/

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