SOS is open-source software licensed under the GPL (v3) for non-commercial academic purposes.  Three external packages included as part of SOS are also licensed for open-source distribution and are covered by the BSD and GPL (v3) licenses, respectively.  See the acknowledgements for details.  For other uses (e.g., commercial, for-profit) please contact the authors (

Blair Armstrong, Christine Watson, David Plaut, 2011-2012