Anales de la Real Sociedad Española de Física y Química Ser. A , Física Volume 94 Issue 2 Issue 1 Volume 93 Issue 3 Issue 2 Issue 1 Volume 92 Issue 3 Issue 2 Issue 1 Volume 91 Issue 3 Issue 2 Issue 1 Volume 90 Issue 3 Issue 2 Issue 1 Volume 89 Issue 3 Issue 2 Issue 1