National Geologic Map Database. at <http://ngmdb.usgs.gov>

Zen, E. -an et al. Bedrock Geologic Map of Massachusetts. USGS Unnumbered Series (1983). at <http://ngmdb.usgs.gov/Prodesc/proddesc_16357.htm>

Robinson, P. & Fernandez, M. Preliminary bedrock geologic map of the Orange 7.5' quadrangle, Massachusetts (including portions of the Millers Falls and Athol 7.5' quadrangles). Open File Report (2008).

Barosh, P. J., Fahey, R. J. & Pease, Maurice Henry, J. Preliminary compilation of the bedrock geology of the land area of the Boston 2 degree sheet, Massachusetts, Connecticut, Rhode Island and New Hampshire. USGS Open File Report (1977). at <http://pubs.er.usgs.gov/publication/ofr77285>

The New England Seismic Network. at <http://quake.bc.edu:8000/index.htm>

Recent New England Earthquakes. at <http://quake.bc.edu:8000/cgi-bin/NESN/recent_events.pl>

Recent New England Earthquakes - Map. at <http://quake.bc.edu:8000/quakes_recent.htm>