Georgakakis, A., Aird, J., Buchner, J., Salvato, M., Menzel, M.-L., Brandt, W. N., McGreer, I. D., Dwelly, T., Mountrichas, G., Koki, C., Georgantopoulos, I., Hsu, L.-T., Merloni, A., Liu, Z., Nandra, K., & Ross, N. P. (2015). The X-ray luminosity function of active galactic nuclei in the redshift interval z=3-5. Monthly Notices of the Royal Astronomical Society, 453(2), 1946-1964. doi:10.1093/mnras/stv1703.