Depending on the journal you are submitting your paper, you can reference the
use of FULLPROF in one of the following forms:
J. Rodriguez-Carvajal, "FULLPROF: A Program for Rietveld Refinement
and Pattern Matching Analysis", Abstracts of the Satellite Meeting
on Powder Diffraction of the XV Congress of the IUCr, p. 127,
Toulouse, France (1990).
J. Rodriguez-Carvajal, FULLPROF version ##### date, ILL (unpublished).
(##### means the inscription on the screen at the beginning of
running the program)
J. Rodriguez-Carvajal, LLB (private communication).
If your problem is concerned with magnetic structure refinement, a short
account on FULLPROF was published recently in Physica B, you can consider
that article as a suitable reference:
J. Rodriguez-Carvajal, "Recent Advances in Magnetic Structure
Determination by Neutron Powder Diffraction", Physica B 192, 55-69
(1993)