Dear all, on the help page for '?sort': 'Method "shell" uses Shellsort ([...] from Sedgewick (1996))' but in the references it is Sedgewick (1986). 1986 seems correct: http://dx.doi.org/10.1016/0196-6774(86)90001-5 Thank you, Enrico -- Enrico Schumann Lucerne, Switzerland http://enricoschumann.net