The first stages of the career of the emperor Pertinax are known from the opening lines of his biography in the Historia Augusta (“Pertinax“, 1.5-2.4). This information was confirmed by an inscription from Brühl near Cologne, which is interesting because – even though it is extremely damaged and only forty-nine letters survive – could be restored almost completely by the German scholar H.G. Kolbe. Having reconstructed the original wording, he even managed to add some details to the outline offered in the Historia Augusta.
You can read it here.