Atlas of monochromatic images of planetary nebulae
  We present an atlas of more than one hundred original images of planetary nebulae (PNe). These images were taken in a narrow-band filter centred on the nebular emission of the [N II] during several observing campaigns using two moderate-aperture telescopes, at the Complejo Astron\'omico El Leoncito (CASLEO), and the Estaci\'on Astrof\'isica de Bosque Alegre (EABA), both in Argentina. The data provided by this atlas represent one of the most extensive image surveys of PNe in [N II]. We compare the new images with those available in the literature, and briefly describe all cases in which our [N II] images reveal new and interesting structures. 
W. A. Weidmann, E. O. Schmidt, R. R. Vena Valdarenas, J. A. Ahumada,   M. G. Volpe and A. Mudrik
astro-ph.SR astro-ph.GA