Gugliotta L, Besses C, Griesshammer M, Harrison C, Kiladjian J-J, Coll R, Smith J, Abhyankar B, Birgegård G. Combination therapy of hydroxycarbamide with anagrelide in patients with essential thrombocythemia in the evaluation of Xagrid® efficacy and long-term safety study. Haematologica 2014; 99(4):679-687; https://doi.org/10.3324/haematol.2012.083097.