1. Forest statistics for New York, 1980;Considine;USDA For. Serv. Resour. Bull. NE-71,1982
2. Forest statistics for Pennsylvania, 1978;Considine;USDA For. Serv. Resour. Bull. NE-65,1980
3. Forest statistics for Ohio, 1979;Dennis;USDA For. Serv. Resour. Bull. NE-68,1981
4. Elementary Statistical Methods for Foresters;Freese,1967
5. State and Metropolitan Area Data Book, 1979;U.S. Bur. Census,1980