Following statement copied from https://calzaferri.dcb.unibe.ch/program/iconedit.html (18.10.2019):
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ICON-EDiT
An Extended Hueckel Molecular Orbital and Oscillator Strength Calculation Package
Copyright  2000, by G. Calzaferri

The programs are free software; you can redistribute and/or modify them under the terms of the GNU General Public License as published by the Free Software Foundation (version 2 of the license).