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.
The Ohio Ecological Food and Farm Association says that Ohio needs stronger regulations on hydraulic fracturing or fracking.
The group, with 3,000 members, says its supports stronger rules than are found in Senate Bill 315, the plan submitted to the Ohio legislature by Gov. John Kasich.
The association wants full chemical disclosure by drillers, wants public participation in the permitting process and wants increased control at the local level.
"Opportunities for short-term economic prosperity should not and cannot come at the expense of our natural resources," said OEFFA spokeswoman MacKenzie Bailey.
Her group supports a healthy and sustainable food system. Many of its members are involved in organic farming.