TY  - JOUR
A1  - Worthen, A. H. & Meek, F. B.
JO  - Geological Survey of Illinois
C1  - 6: 489–532, pls 23–33
TI  - Palaeontology of Illinois, Section 2, Descriptions of invertebrates.
UR  - https://www.biodiversitylibrary.org/page/40423327
PY  - 1875
Y2  - 2026-09-15
ER  -