T. A.K. Al-Allaf, L. J. Rashan, R. F. Khuzaie, and W. F. Halaseh, “Synthesis, Characterization and Cytotoxic Activity of New Platinum(II) Complexes with some Nitrogen Containing Ligands, Part 1: With β-Carboline Alkaloids”, ajc, vol. 8, no. 3, pp. 505–512, Jul. 2012.