Chesapeake Energy Corp,the Oklahoma-based firm is the No. 1 driller in Ohio.
Rig Count Interactive Map by Baker Hughes, an energy services company.
Shale Sheet Fracking, a Youngstown Vindicator blog.
The Ohio Environmental Council, a statewide eco-group based in Columbus.
Earthjustice, a national eco-group.
People's Oil and Gas Collaborative-Ohio, a grass-roots group in Northeast Ohio.
Concerned Citizens of Medina County, a grass-roots group.
No Frack Ohio, a Columbus-based grass-roots group.
Fracking: Gas Drilling's Environmental Threat by ProPublica, an online journalism site.
Pipeline, blog from Pittsburgh Post-Gazette on Marcellus shale drilling.
Allegheny Front, environmental public radio for Western Pennsylvania.
Last week, North Dakota landowners filed 10 class-action lawsuits seeking millions of dollars in lost royalties from some of the biggest drilling companies, the New York Times reported.
The owners of the mineral rights are unhappy that the companies have been burning or flaring natural gas.
The companies have been burning the natural gas because there are no pipelines for transporting it. About 30 percent of the natural gas from North Dakota wells are burned.
That means that about $100 million a month is lost.
The suits seek to force the drillers to pay royalties on the natural gas being burned.
The North Dakota Petroleum Council recently called to reduce flaring of natural gas in the sttae.