Year book for 1915 :
administrative report and economic and geological papers.
APA Citation
Illinois State Geological Survey. (1916). Year book for 1915: administrative report and economic and geological papers. Urbana, Ill.: Illinois State Geological Survey, University of Illinois.
MLA Citation
Illinois State Geological Survey. Year Book for 1915: Administrative Report And Economic And Geological Papers. Urbana, Ill.: Illinois State Geological Survey, University of Illinois, 1916.
Warning: These citations may not always be complete (especially for serials).