Baars, J. W., Durant, C. J., Guinot, B., Landolt-Börnstein, Beer, H., Graser, U., & Voigt, H. (1993). Astronomy and astrophysics: Extension and supplement to volume 2 / editor: H. H. Voigt, contributors: J. W. Baars, H. Beer, C. J. Durant, U. Graser, B. Guinot [and 21 others]. Berlin: Springer.

Baars, Jan W., C. J. Durant, B. Guinot, Landolt-Börnstein, H. Beer, U. Graser, andfavorite Hans-Heinrich Voigt. Astronomy and Astrophysics: Extension and Supplement to Volume 2 / Editor: H. H. Voigt, Contributors: J. W. Baars, H. Beer, C. J. Durant, U. Graser, B. Guinot [and 21 Others]. Berlin: Springer, 1993.

Baars, Jan W., et al. Astronomy and Astrophysics: Extension and Supplement to Volume 2 / Editor: H. H. Voigt, Contributors: J. W. Baars, H. Beer, C. J. Durant, U. Graser, B. Guinot [and 21 Others]. Berlin: Springer, 1993.