GLOBE Observer Data: 2016–2019 oleh Helen M. Amos, Matthew J. Starke, Tina M. Rogerson, Marilé Colón Robles, Travis Andersen, Rebecca Boger, Brian A. Campbell, Russanne D. Low, Peder Nelson, David Overoye, Jessica E. Taylor, Kristen L. Weaver, Trena M. Ferrell, Holli Kohl, Theresa G. Schwerin