“ Mention should also be made of the Commentarii Regum, containing decrees concerning the functions and privileges of the kings, and forming a record of the acts of the king in his capacity of priest. They were drawn up in historical times like the so-called leges regiae (jus Papirianum) , supposed to contain the decrees and decisions of the Roman kings.
See the exhaustive article by A. von Premerstein in Pauly-Wissowa, Realencyclopädie (1901) ; Teuffel-Schwabe, Hist. of Roman Lit. (Eng. trans.) ”