Londish, D., Croom, S., Boyle, B., Shanks, T., Outram, P., Sadler, E., …Maxted, P. (2002). The 2QZ BL Lac survey. Monthly Notices of the Royal Astronomical Society, 334, 941-957. https://doi.org/10.1046/j.1365-8711.2002.05578.x