1. Total Petroleum Hydrocarbon Criteria Working Group (TPHCWG) (1997) Development of Fraction Specific References Doses (RfDs) and Reference Concentrations (RfCs) for Total Petroleum Hydrocarbons (TPH), vol. 4. Amherst, MA: Amherst Scientific Publishers.
2. Total Petroleum Hydrocarbon Criteria Working Group (TPHCWG) (1999) Human Health Risk-Based Evaluation of Petroleum Release Sites: Implementing the Working Group Approach, vol. 5. Amherst, MA: Amherst Scientific Publishers.