Noxious weeds in Illinois; description and control. Illinois noxious weed law 2, 4-D and related Herbicide act.

Revisions in 1963 and 1970.

Non-point source loading of nutrients in Illinois /

Bibliography: p. 30.

Oil and gas developments in Illinois, 1987 /

Mode of access: Internet.

Oil and gas drilling in Illinois; monthly report.

At head of title, -Dec. 1978: State of Illinois, Dept. of Registration and Education; Jan. 1979-: State of Illinois, Illinois Institute of Natural Resources.

Operating statistics of telephone companies in Illinois /

Description based on: year ended Dec. 31, 1979; title from cover.

Older women in Illinois : the differences they face.

Cover title.

OPPortunities to prevent pollution in Illinois.

Subtitle varies.

Opportunities for ethanol - gasohol research in Illinois.

Bibliography: p. 49.

Papers in Illinois history and transactions for the year ... /

Vols. for 1937-1942 issued without series note but constitute no. 44-49 of the Society's Publication.

Osteoporosis in Illinois : analysis of hospital discharge records from 1992 to 1995 /

"December 1997. "

Outdoor recreation in Illinois /

Cover title: Outdoor recreation in Illinois : the statewide comprehensive outdoor recreation plan.

Outdoor recreation in Illinois, the ... policy plan.

"Public review draft."

Osteoporosis in Illinois, 2003.

"3/03"--Colophon.

Phase II report : preliminary investigation of small-scale hydropower potential at five sites in Illinois /

"Project no. 80.190."

Pest and pesticide management in Illinois agriculture : status and policy options /

"Contract IP 3."