Eubacteria None 2015 Eubacteria None 2015 Eubacteria None 2015 Bacteria (None 2015) Woese et al. 1990 Parker C.T. Tindall B.J. Garrity G.M. International Code of Nomenclature of Prokaryotes 2019 69 1A S1 S111 International Journal of Systematic and Evolutionary Microbiology Int J Syst Evol Microbiol 1466-5026 1466-5034 10.1099/ijsem.0.000778 26596770 Woese C.R. Kandler O. Wheelis M.L. Towards a natural system of organisms: proposal for the domains Archaea, Bacteria, and Eucarya 1990 87 12 4576 4579 Proceedings of the National Academy of Sciences of the United States of America Proc Natl Acad Sci U S A 0027-8424 1091-6490 10.1073/pnas.87.12.4576 2112744 No reference is available 2015 The urkingdom "eubacteria" was never formally proposed and therefore lacks standing in nomenclature.