Hyperfine structure in the atomic spectrum of niobium - I: Experimental investigation A. Bouzed, S. Kröger, D. Zimmermann, H.-D. Kronfeldt and G. Guthöhrlein Eur. Phys. J. D, 23 1 (2003) 57-62 Published online: 04 February 2003 DOI: 10.1140/epjd/e2003-00026-8