http://www.zemax.com/kb en-us N/A support@zemax.com Fri, 04 Jul 2008 19:33:06 PDT 20 http://www.zemax.com/kb/articles/111/1/How-To-Write-ZEMAX-Extensions-in-FORTRAN/Page1.html no@spam.com (Anthony Richards) http://www.zemax.com/kb/articles/111/1/How-To-Write-ZEMAX-Extensions-in-FORTRAN/Page1.html