1. Barnes MC, Todd AH, Whitney Lilja R, Barten PK (2009) Forests, water and people: drinking water supply and forest lands in the Northeast and Midwest United States. USDA Forest science, Northeastern Area State and Private Forestry, p 71
2. Brower J, Zar J (1997) Field and laboratory methods for general ecology, 4th edn. Brown Company Publishers, New York, p 51
3. Calder IR (2007) Forests and water—ensuring forest benefits outweight water costs. For Ecol Manage 251:110–120
4. Calder IR, Hofer T, Vermont S, Warren P (2007) Towards a new understanding of forests and water. Unasylva 229(58):3–10
5. Dudley N, Stolton S (2003) Running pure: the importance of forest protected areas to drinking water. Alliance for Forest Conservation and Sustainable, London, p 114