1. Abhyankar, S.: On the ramification of algebraic functions. Am. J. Math. 77, 575–592 (1955)
2. Abramovich, D.: A linear lower bound on the gonality of modular curves. Int. Math. Res. Not. 20, 1005–1011 (1996)
3. Abramovich, D., Harris, J.: Abelian varieties and curves in $$W_d(C)$$ W d ( C ) . Compositio Math. 78(2), 227–238 (1991)
4. Amini, O., Baker, M., Brugallé, E., Rabinoff, J.: Lifting harmonic morphisms I: metrized complexes and Berkovich skeleta (2013, preprint). arxiv:1303.4812
5. Amini, O., Baker, M., Brugallé, E., Rabinoff, J.: Lifting harmonic morphisms II: tropical curves and metrized complexes (2014, preprint). arXiv:1404.3390