1. S. Agmon, Spectral properties of Schrödinger operators and scattering theory, Ann. Scoula. Norm. Sup. Pisa Ser. 4 (1975), 151–218.
2. S. Agmon and L. Hörmander, Asymptotic properties of solutions of differential equations with simple characteristics, J. d’Analyse Math. 30 (1976), 1–38.
3. Z.S. Agranovich and V.A. Marchenko, The Inverse Problem of Scattering Theory, Gordon and Breach, New York, 1963.
4. R. Beals and R.R. Coifman, Multidimensional inverse scatterings and nonlinear partial differential equations, Proc. Symp. Pure Math. 43 (1985), 45–70.
5. M.I. Belishev and Y.V. Kurylev, To the reconstruction of a Riemannian manifold via its spectral data (BC-Method), Commun. in P.D.E. 17 (1992), 767–804.