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.
Chesapeake Energy Corp. is one of the "100 Best Companies to Work For," according to Fortune Magazine.
The Oklahoma-based energy company is the top player in Ohio's Utica shale.
It was ranked No. 18 on the list, up from 32 a year ago.
It is the company's fifth consecutive year on the Fortune Magazine list.
The company has 12,500 employees.
It hired 4,800 new employees in 2011 and expects to hire an additional 5,000 new workers in 2012.
It expects to hire 1,200 new workers in its eastern division that includes Ohio.
The company has a Canton office and has leased about 1.5 million acres in eastern Ohio.