Multiple drug combinations of bortezomib, lenalidomide, and thalidomide for first‐line treatment in adults with transplant‐ineligible multiple myeloma: A network meta‐analysis - Piechotta, V; Jakob, T; Langer, P; Monsef, I; Scheid, C; Estcourt, L; Ocheni, S; Theurich, S; Kuhr, K; Scheckel, B; Adams, A; Skoetz, N (Cochrane Database of Systematic Reviews, 2019)