1975  Diaboloceras involutum Nassichuk: 151, text-fig.54,
           pl.15 fig.3,7,9, pl.17 fig.4,5,6,9.
cf.  1988  Diaboloceras cf. involutum.-Liang & Wang: pl.6
           fig.4a.b.
cf.  1991  Diaboloceras cf. involutum.-Liang & Wang: 128,
           text-fig.104, pl.40 fig.14, 15.