1. Akhiezer, N., Glazman, I.: Theory of linear operators in Hilbert space, vol. I, II. Monographs and Studies in Mathematics, 9, 10. Publ. in association with Scottish Academic Press, Edinburgh (Transl. from the 3rd Russian ed. by E.R. Dawson and W.N. Everitt). Boston: Pitman Advanced Publishing Program (1981)
2. Ascanelli, A., Süß, A: Random-field solutions to linear hyperbolic stochastic partial differential equations with variable coefficients (2014). arXiv:1401.5783
3. Barchielli, A., Gregoratti, M.: Quantum Trajectories and Measurements in Continuous Time. Springer, Berlin (2009)
4. Bitsadze, A.V.: Equations of the Mixed Type. Pergamon Press, Paris (1964)
5. Conus, D., Dalang, R.C.: The non-linear stochastic wave equation in high dimensions. Electron. J. Probab. 13, 629–670 (2008)