523.74 Ada I Adams, Walter Sydney, 1876- An investigation of the rotation period of the sun by spectroscopic methods by Walter S. Adams, assisted by Jennie B. Lasby. Washington, Carnegie Institution of Washington, 1911 132 p. gráficos, láms., tablas. 29 cm. (Carnegie Institution of Washington. Publication nº 138) ´´Bibliographical references´´: p. 132