Aftermarket catalytic convertors : guide to their purchase, installation, and use /

"January 1989."

An intensive survey of the Mackinaw River Basin, 1987 /

"September 1988."--Cover.

An intensive survey of the Henderson Creek Basin, 1994 /

"February, 1996."

An intensive survey of the Indian Creek Basin, 1992 /

"IEPA/WPC/95-2."--Cover.

An intensive survey of the Elkhorn Creek Basin, 1985.

"IEPA/WPC/88-017."--Cover.

An intensive survey of the Pecatonica River Basin, 1984-1985.

"February 1988."--Cover.

An assessment of the water quality of the Rock River Basin derived from a biological investigation /

"Prepared for the Illinois Environmental Protection Agency."

An intensive survey of the Big Muddy main stem from Rend Lake to the Mississippi River Summer 1988 /

"IEPA/WPC/91-56."--Cover.

An intensive survey of the Embarras River Basin, 1987 /

"IEPA/WPC/89-212."--Cover.

An intensive survey of the Bay Creek Watershed, July 1992 /

"IEPA/WPC/95-020"--Cover.

An intensive survey of the Big Muddy River Basin: summer 1995/

"March 1997."

An intensive survey of the Little Vermilion River as affected by seasonal variation, 1992 /

"March 1993."

An intensive survey of the Edwards River and Pope Creek, 1991 /

"October 1993."--Cover.

An intensive survey of Rock River tributaries, 1985.

"February 1988."--Cover.

An intensive survey of the Cache River Basin, summer 1992 /

"IEPA/WPC/95-013."--Cover.