The subject of the paper is the old and well-known linear least squares met
hod for determining the lattice dimension of a crystalline phase from the p
eak locations of a powder diffraction pattern. Approximations, limits, and
extensions of the method are discussed with reference to the assignment of
hkl indices to an experimental multiphase pattern. (C) 1999 International C
entre for Diffraction Data. [S0885-7156(99)00201-8].