Tremblay, G. R., Oonk, J. R., Combes, F., Salomé, P., O'Dea, C. P., Baum, S. A., …Wise, M. W. (2016). Cold, clumpy accretion onto an active supermassive black hole. Nature, 534(7606), 218-221. https://doi.org/10.1038/nature17969