Landslides in Pennsylvania /

od Delano, Helen L.
Harrisburg, Pa. : Pennsylvania Geological Survey, 2003
2nd ed.

Landslide susceptibility in the Williamsport 1- by 2-degree quadrangle, Pennsylvania /

od Delano, Helen L.
Harrisburg, [Pa] : Dept. of Conservation and Natural Resources, 1999

Landslides in Pennsylvania /

od Delano, Helen L.
Harrisburg, Pa. : Pennsylvania Geological Survey, 2001
2nd ed.

Landslide susceptibility in the Williamsport 1- by 2-degree quadrangle, Pennsylvania /

od Delano, Helen L.
Harrisburg : Pennsylvania Geological Survey, 1999
Fourth series.

Landslide susceptibility in the Williamsport 1- by 2-degree quadrangle, Pennsylvania /

od Delano, Helen L.
Harrisburg : Pennsylvania Geological Survey, 1999
4th series.

Presque Isle State Park, Erie County : a dynamic interface of water and land /

od Delano, Helen L.
Harrisburg, Pa.] : Commonwealth of Pennsylvania, Dept. of Environmental Resources, Office of Resources Management, Bureau of Topographic and Geologic Survey and Bureau of State Parks, 1991

Landslide susceptibility in the Williamsport 1- by 2-degree quadrangle, Pennsylvania /

od Delano, Helen L.
Harrisburg : Pennsylvania Geological Survey, 1999

Landslides in Pennsylvania /

od Delano, Helen L.
Harrisburg, Pa. : Pennsylvania Geological Survey, 2001
2nd ed.

Presque Isle State Park, Erie County : a dynamic interface of water and land

od Delano, Helen L.
[Harrisburg, Pa.] : Commonwealth of Pennsylvania, Department of Environmental Resources, Office of Resources Management, Bureau of Topographic and Geologic Survey and Bureau of State Parks, 1991

Landslides in Pennsylvania /

od Delano, Helen L.
Harrisburg, Pa. : Pennsylvania Geological Survey, 2001
Second edition.

Presque Isle State Park, Erie County : a dynamic interface of water and land /

od Delano, Helen L.
[Harrisburg, Pa.] : Commonwealth of Pennsylvania, Dept. of Environmental Resources, Office of Resources Management, Bureau of Topographic and Geologic Survey and Bureau of State Parks, 1991

Landslide susceptibility in the Williamsport 1- by 2-degree quadrangle, Pennsylvania /

od Delano, Helen L.
Harrisburg : Pennsylvania Geological Survey, 1999
4th series.

Landslide susceptibility in the Williamsport 1- by 2-degree quadrangle, Pennsylvania /

od Delano, Helen L.
Harrisburg, Pa. : Pennsylvania, Bureau of Topographic and Geologic Survey, 1999
4th series.

Landslides in Pennsylvania /

od Delano, Helen L.
Harrisburg, Pa. : Pennsylvania Geological Survey, 2001
2nd ed.

The 2008-2009 earthquake swarm near Dillsburg, Pennsylvania /

od Kim, Won-Young, 1950-, Gold, Mitchell (Geologist), Scharnberger, Charles K. (Charles Kirby), 1943-, Jones, Jeri L., Delano, Helen L.
Middletown, Pennsylvania : Commonwealth of Pennsylvania, Department of Conservation and Natural Resources, Bureau of Topographic and Geologic Survey, 2009

Geomorphology in the northern Cumberland Valley PA, including the Carlisle Deluge of 1779 /

Harrisburg : Harrisburg Area Geological Society, 1998