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"Messier 80". SEDS Messier Catalog. Archived from the original on April 30, 2022. Retrieved April 30, 2022.
"Messier 80". SEDS Messier Database. Students for the Exploration and Development of Space. Archived from the original on January 14, 2022. Retrieved December 19, 2021.
"Messier 80". SEDS Messier Catalog. Archived from the original on April 30, 2022. Retrieved April 30, 2022.
"Messier 80". SEDS Messier Database. Students for the Exploration and Development of Space. Archived from the original on January 14, 2022. Retrieved December 19, 2021.