W. E. Ernst, J. Kändler, C. Noda, J. S. McKillop, and R. N. Zare, “Hyperfine Structure of the BaI X 2Σ+ and C 2Π States,” J. Chem. Phys. 85, 3735-3743 (1986); see also C. A. Leach, W. E. Ernst, J. Kändler, C. Noda, J. S. McKillop and R. N. Zare, “Erratum: Hyperfine Structure of the BaI X 2Σ+ and C 2Π States,” J. Chem. Phys. 95, 9433 (1991).