Remeasurement of the profile of the characteristic Cu Kα emission line with high precision and accuracy. Erratum

Two errors in the paper by Härtwig, Hölzer, Wolf & Förster [J. Appl. Cryst. (1993), 26, 539–548] are corrected. On p. 540, the fifth line after equation (1) should read `δ₁, δ₂ and κ are small tilts of the crystals and the collimator, respectively'. In the reference list, the reference to Wilson (1958) should read Wilson, A. J. C. (1958). Proc. Phys. Soc. London, 72, 924–925.