Encyclopedia of mineral namesWilliam Blackburn, William H. Dennen · First published 1998Open the Tome
Bedrock geologic map of the Marblehead North quadrangle, Essex County, MassachusettsWilliam H. Dennen · First published 1991Open the Tome
Bedrock geology of the Cape Ann Area, MassachusettsWilliam H. Dennen · First published 1981Open the Tome
