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.
A former researcher at the Colorado School of Mines who left after coming under fire from drilling interests after he made critical comments about hydraulic fracturing or fracking has lost his job at the University of Wyoming.
Geoffrey Thyne lost his Wyoming job after an energy-drilling association expressed unhappiness with recent critical comments made by Thyne.
That has raised questions about academic freedom and the industry's influence in academia.
Click here to read the story in the Boulder Weekly.