@article{Severgnini:2024fe, author = "Severgnini, Paola and De Rosa, Alessandra and Vignali, Cristian and Mannucci, Filippo", title = "{Dual and binary supermassive black holes}", doi = "10.22323/1.447.0061", journal = "PoS", year = 2024, volume = "MULTIF2023", pages = "061" }