Johnsen HE, Bøgsted M, Schmitz A, Bødker JS, El-Galaly TC, Johansen P, Valent P, Zojer N, Van Valckenborgh E, Vanderkerken K, van Duin M, Sonneveld P, Perez-Andres M, Orfao A, Dybkær K. The myeloma stem cell concept, revisited: from phenomenology to operational terms. Haematologica 2016; 101(12):1451-1459; https://doi.org/10.3324/haematol.2015.138826.