Bruserud, Ø. “Effect of Dipyridamole, Theophyllamine and Verapamil on Spontaneous in Vitro Proliferation of Myelogenous Leukaemia Cells”. Acta Oncologica, vol. 31, no. 1, Jan. 1992, pp. 53-58, doi:10.3109/02841869209088266.