[379] Perm, Abkürzung für Permische Formation (s.d.).
Brockhaus-1911: Perm [2]
Herder-1854: Perm
Lueger-1904: Perm, Permische Formation
Meyers-1905: Perm [3] · Perm [2] · Perm [1]
Pierer-1857: Perm [2] · Perm [1]