Pennsylvania

Bevan, B.W. (1980). Geophysical Survey at Apppomattox Manor. Ms. on file, Mid-Atlantic Regional Office, National Park Service, Philadelphia.

Bevan, B. W. (1977). Ground-Penetrating Radar at Valley Forge. Ms. on file, Geophysical Survey Systems, North Salem, New Hampshire.

Parrington, M. (1979). Geophysical and Aerial Prospecting Techniques at Valley Forge National Historic Park, Pennsylvania. Journal of Field Archaeology 6(2):193-201.