Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA
Solar Physics Branch, Naval Research Laboratory, Washington, DC 20375, USA
NASA Goddard Space Flight Center, Code 682, Greenbelt, MD 20771, USA
University of Florence, Arcetri Astrophysical Observatory, Largo Fermi 5, Florence, 50125 Italy
Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA
Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA
Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA
Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA; Torino Astronomical Observatory, Pino Torinese, Turin, 10025 Italy
Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA
Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA
University of Florence, Arcetri Astrophysical Observatory, Largo Fermi 5, Florence, 50125 Italy
Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA
Solar Physics Branch, Naval Research Laboratory, Washington, DC 20375, USA
Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA
Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA