“Galactic confusion and the detection of 1665 and 1667 MHz OH lines inthe neighborhood of planetary nebulae”., RMxAA, vol. 14, no. 1, pp. 567–572, Jan. 1987, Accessed: Dec. 09, 2025. [Online]. Available: https://astronomia.unam.mx/journals/rmxaa/article/view/1987rmxaa..14..567t