Interstellar deuterated ammonia: from NH3 to ND3 E. Roueff, D. C. Lis, F. F. S. van der Tak, M. Gerin and P. F. Goldsmith A&A, 438 2 (2005) 585-598 Published online: 08 July 2005 DOI: 10.1051/0004-6361:20052724