1. School of Physics and Astronomy, University of St Andrews , North Haugh, St Andrews KY16 9SS, UK
2. The William H. Miller III Department of Physics & Astronomy, Johns Hopkins University , Baltimore, MD 21218, USA
3. Universidad Nacional Autónoma de México, Instituto de Astronomía , A.P. 70-264, 04510, Mexico, D.F., Mexico
4. Departamento de Astronomia, Instituto de Física, Universidade Federal do Rio Grande do Sul , CP 15051, 91501-970, Porto Alegre, RS, Brazil
5. Laboratório Interinstitucional de e-Astronomia - LIneA , Rua Gal. José Cristino 77, Rio de Janeiro, RJ - 20921-400, Brazil
6. Departamento de Física, CCNE, Universidade Federal de Santa Maria , 97105-900, Santa Maria, RS, Brazil
7. Department of Physics & Astronomy, University of Utah , Salt Lake City, UT, 84112, USA