1. VIOLATIONS PER WELL AMONG PA OPERATORS;Matt Kelso;FracTracker.org, last modified October,2013
2. Fracking's Environmental Impacts: Water;Les Stone;#:~:text=Contamination%20of%20Water%20Wells%20and
3. Fracking's Most Wanted: Lifting the Veil on Oil and Gas Company Spills and Violations;Nrdc;Natural Resources Defense Council),2015
4. The Costs of Fracking, The Price Tag of Dirty Drilling's Environmental Damage;T Dutzik;Environment America Research & Policy Center,2022
5. Fracking 101. Be a force for the future;M Denchak;NRDC,2019