S. Ryland

A circadian rhythm in the effect of thyroxine in the stimulation of metamorphosis in the African Clawed Frog, Xenopus laevis

John T. Bums, Renee Patyna, S. Ryland, 1987 .

Gravity anomalies in the galapagos islands area.

T. Simkin, J. R. Cochran, A. Watts, 1974, Science.

Gravitational Evidence for a Low-Density Mass beneath the Gal�pagos Islands

T. Simkin, K. Howard, J. E. Case, 1973, Science.