Trilobites of the Chicago region
By: by Charles and Patricia Armstrong.
Contributors: Armstrong, Patricia Kay Stoddard, 1936- joint author.
Published: 1962
Place of publication: [Naperville? Ill.]
Language: eng
Number of pages: 59
Subjects: Trilobites.; Paleontology -- Silurian.; Paleontology -- Illinois.
Notes: Includes bibliography.