Las mariposas entre los antiguos mexicanos

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La historia de la humanidad es rica, a través de miles de años, en eventos que han marcado esa historia. Hechos que han puesto una bisagra en el desarrollo de la humanidad y que señalan un antes y un después de los mismos. Cualquiera podría preguntarse cuál de esos eventos considera el más importante o el que ha provocado los cambios más profundos. Seguramente habría una inmensa diversidad de opiniones y un enorme abanico de hechos que son considerados así. Se trata obviamente de una materia muy opinable y todas las ideas son respetables. Luego de analizar largamente el tema, he...

"Inventario de los libros que han tenido ingreso en la secretaría de la Real academía," 1922-29, with v. 83, 85, 87, 89, 91-92, 96, 99.

This is the second of three volumes which together contain the complete range of Lord Rutherford’s scientific papers, incorporating in addition addresses, general lectures, letters to editors, accounts of his scientific work and personal recollections by friends and colleagues. Volume two, first published in 1963, includes the papers published by Rutherford when professor of Physics at Manchester, 1907 to 1919. While the work of his laboratory ranged over the whole field of radioactivity, he himself devoted much effort to questions concerning the nature and properties of the α particle....