Gaspers, Serge, Neeldhara Misra, Sebastian Ordyniak, Stefan Szeider, and Stanislav Zivny. 2014. “Backdoors into Heterogeneous Classes of SAT and CSP”. Proceedings of the AAAI Conference on Artificial Intelligence 28 (1). https://doi.org/10.1609/aaai.v28i1.9111.