Rationale and design of the German-Speaking Myeloma Multicenter Group (GMMG) trial ReLApsE: a randomized, open, multicenter phase III trial of lenalidomide/dexamethasone versus lenalidomide/dexamethasone plus subsequent autologous stem cell transplantation and lenalidomide maintenance in patients with relapsed multiple myeloma - Bärtsch, Marc-Andrea; Schlenzka, Jana; Mai, Elias K.; Merz, Maximilian; Hillengaß, Jens; Raab, Marc-Steffen; Hose, Dirk; Wuchter, Patrick; Ho, Anthony Dick; Jauch, Anna; Luntz, Steffen P.; Klein, Stefan; et al. (BioMed Central; Springer, 2016)