Tomb of Johannes Monachus
Abbey of Saint Victor, Paris
Johannes Monachus, In sextum decretalium glossa aurea nuncupata (Venetiis: 1585) to VI 1.6.4 (Vt circa electiones) fol. 64va-64vb, s.v. edicto perpetuo,  Munich, Staatsbibliothek 6353, fol. 21rb s.v. edicto perpetuo, Vat. Borgh. 283, fol. 15ra, s.v. edicto perpetuo:
Sunt enim sex modi cognoscendi ius commune:
 Primus est si mittatur venerabili cetui.
Secundus si edicti vocabulo nuncupetur, ut hic
      vel quia dicit hac edictali.
Tertius si praecipitur per omnes populos diuulgari
      scriptura publice procedente.
Quartus si dicatur idem in similibus obseruandum.
Quintus si lex vel canon appellatur et generalis.
Sextus si iubetur expresse ad omnes pertinere.

There are six ways to recognize a ius commune:

The first is that it was sent to an ancient assembly.

Second, is if it is proclaimed with the name "edict" as

     in this decretal or because it contains "by this edict."

Third, if it is ordered to be spread publicly by written word.

Fourth, if it is said that it must be observed in similar cases.

Fifth, if the law or the canon is called general.

Sixth, if it is commanded expressly that it pertains to everyone.