1. Abbondandolo A., Majer P.: A Morse complex for infinite dimensional manifolds. I. Adv. Math. 197(2), 321–410 (2005)
2. Abbondandolo A., Mejer P.: A Morse complex for Lorentzian geodesics. Asian J. Math. 12, 299–320 (2008)
3. Abraham, R.: Bumpy metrics. In: Global Analysis (Proc. Sympos. Pure Math., Vol. XIV, Berkeley, Calif., 1968), Providence, R.I.: Amer. Math. Soc., 1970, pp. 1–3
4. Anosov D.V.: Generic properties of closed geodesics. Izv. Akad. Nauk SSSR Ser. Mat. 46(4), 675–709, 896 (1982)
5. Abraham R., Robbin J.: Transversal mappings and flows. W. A. Benjamin, New York (1967)