S. V.  Shedge, Carmona-Espindola, J., Pal, S., and Koster, A. M., ?Comparison of the auxiliary density perturbation theory and the noniterative approximation to the coupled perturbed kohn-sham method: case study of the polarizabilities of disubstituted azoarene molecules?, Journal of Physical Chemistry A, vol. 114, no. 6, pp. 2357-2364, 2010.