Steele, P. R. Optical and Interpretative Astronomy, MPI for Extraterrestrial Physics, Max Planck Society;
Steele, P. R., Burleigh, M. R., Barstow, M. A., Jameson, R. F., & Dobbie, P. D. (2011). Ultracool companions to white dwarfs. In K. Werner, & T. Rauch (Eds.), 17th European White Dwarf Workshop (pp. 384-389).