Richer, M. G., S. h. Báez, and J. A. López. “What Can We Learn About the Kinematics of Bright Extragalactic Planetary Nebulae?”. Revista Mexicana de Astronomía y Astrofísica 45, no. 2 (November 22, 2010). Accessed May 19, 2024. https://journals.unam.mx/index.php/revmexaa/article/view/20676.