Evidence for Hierarchical Black Hole Mergers in the Second LIGO-Virgo Gravitational Wave Catalog

1. Kimball, C.
2. Talbot, C.
3. Berry, C.P.L.
4. Zevin, M.
5. Thrane, E.
6. Kalogera, V.
7. Buscicchio, R.
8. Carney, M.
9. Dent, T.
10. Middleton, H.
11. Payne, E.
12. Veitch, J.
13. Williams, D.