Dumb Scala question

Sorry to be a dope, but what does "NM" mean in chord notation in Scala?

Examples:
NM Erlich Split Ninth 4:6:7:9
NM Quasi-Stable Twin Twelfth 1:3:9
8/5 Chord, NM Trine "8|5-4" 2:3:4

Thanks,
Jake