doi.org/10.1371/journal.pone.0158342
PLoS ONE
Algorithms and Complexity

van der Gulik, P., & Hoff, W. (2016). Anticodon modifications in the tRNA set of LUCA and the fundamental regularity in the Standard Genetic Code. PLoS ONE, 11(7), e0158342:1–e0158342:21. doi:10.1371/journal.pone.0158342