D. R. Spydell

Principal facts for two-hundred-thirty-three gravity stations near the Three Sisters Wilderness Area, Oregon

D. Williams, C. Finn, D. R. Spydell, 1985 .

Principal facts for 382 gravity stations in Lassen Volcanic National Park and vicinity, California

R. Saltus, R. Jachens, D. R. Spydell, 1983 .