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 Associated Press reports from Poland that seven people including government officials have been charged with corruption in the granting of licenses for shale gas exploration in that European country.
Bribes of tens of thousands of ziotys were allegedly handed out in the second half of 2011 alone, officials said.
The Internal Security Agency said those arrested included three Environmental Ministry officials, an employee of the state Geology Institute and three representatives of companies involved in shale exploration.
The charges were suspicion of involvement in bribery.
Poland has issued more than 100 licenses for shale exploration to international companies including Exxon Mobil, Chevron, ConocoPhillips and Petrolinvest, the AP reported.
RGES WERE SUSPICION OF INVOLVEMENT IN BRIBERY.