License: GPL Version 3. 

Prior versions of the spg algorithm are licensed under GPL version 2 or later 
and are available at the TANGO project 
<http://www.ime.usp.br/~egbirgin/tango/downloads.php>

The sane and dfsane algorithms are release under GPL version 3 with the
agreement of Marcos Raydan and co-authors, who retain copyright on the
original work. 

Significant modification included  here are Copyright 2008, Ravi Varadhan.
