M. Ehrhardt, "Beharrlichkeit 'zahlt' sich aus" in Zum 25 jährigen Jubiläum, Bergische Blätter, 2011.

A. Mezentsev, A. Pomelnikov and M. Ehrhardt, "Efficient numerical valuation of continuous installment options", Advances in Applied Mathematics and Mechanics, vol. 3, no. 2, pp. 141--164, 2011. Cambridge University Press.

M. Beitz, M. Ehrhardt and others, "A new method for stress testing on investment products", The Risk of Investment Products: From Product Innovation to Risk Compliance, pp. 225, 2011. World Scientific.

M. Clemens, S. Sch\"ops, H. de Gersem and A. Bartel, "Decomposition and Regularization of Nonlinear Anisotropic Curl-Curl DAEs", COMPEL, vol. 30, no. 6, pp. 1701--1714, 2011.

P. Klein, X. Antoine, C. Besse and M. Ehrhardt, "Absorbing boundary conditions for solving N-dimensional stationary Schrödinger equations with unbounded potentials and nonlinearities", Communications in Computational Physics, vol. 10, no. 5, pp. 1280--1304, 2011. Cambridge University Press.