Binary planetary nebulae nuclei towards the Galactic bulge - I. Sample discovery, period distribution, and binary fractionB. Miszalski, A. Acker, A. F. J. Moffat, Q. A. Parker and A. UdalskiA&A, 496 3 (2009) 813-825DOI: https://doi.org/10.1051/0004-6361/200811380
