“…On the site DP line, the DK PCA displays an inactive-active phase transition at the critical point p * 1 = p * 2 = 0.705 489(4) [16], corresponding to ε * = 0.294 511(4), within the rigorous bounds mentioned before (the numbers between parentheses indicate the uncertainty in the last digit or digits of the data). Curiously, the relationship between Stavskaya's PCA and the DK PCA seems to have gone unnoticed in previous investigations [6][7][8][9][10][11], although a coupling scheme with an "independent oriented percolation" process equivalent with site DP was used in [8]. It is worth mentioning that Stavskaya's model, together with another PCA introduced by the same epoch, Vasil'ev's model [6,17]which corresponds to the p 2 = 0 line in the DK PCA or, equivalently, to a probabilistic version of CA rule 18 in Wolfram's classification scheme [18]-predates the DK PCA and related models by almost two decades, but did not receive much attention, not even when CA and PCA reentered the mainstream scientific agenda in the 1980s.…”