Woese, C. R.; Balch, W. E.; Magrum, L. J.; Fox, G. E.; Wolfe, R. S. (august 1977). „An ancient divergence among the bacteria”. Journal of Molecular Evolution. 9 (4): 305–311. Bibcode:1977JMolE...9..305B. doi:10.1007/BF01796092. PMID408502.
Roger, A.J.; Simpson, A.G.B. (). „Evolution: Revisiting the Root of the Eukaryote Tree”. Current Biology. 19 (4): R165–7. doi:10.1016/j.cub.2008.12.032. PMID19243692.
Woese, C. R.; Balch, W. E.; Magrum, L. J.; Fox, G. E.; Wolfe, R. S. (august 1977). „An ancient divergence among the bacteria”. Journal of Molecular Evolution. 9 (4): 305–311. Bibcode:1977JMolE...9..305B. doi:10.1007/BF01796092. PMID408502.
Scamardella, Joseph M. (). „Not plants or animals: a brief history of the origin of Kingdoms Protozoa, Protista and Protoctista”. International Microbiology. 2 (4): 207–16. PMID10943416.
Woese, C. R.; Balch, W. E.; Magrum, L. J.; Fox, G. E.; Wolfe, R. S. (august 1977). „An ancient divergence among the bacteria”. Journal of Molecular Evolution. 9 (4): 305–311. Bibcode:1977JMolE...9..305B. doi:10.1007/BF01796092. PMID408502.
Roger, A.J.; Simpson, A.G.B. (). „Evolution: Revisiting the Root of the Eukaryote Tree”. Current Biology. 19 (4): R165–7. doi:10.1016/j.cub.2008.12.032. PMID19243692.