-------------------
copyright notices 
-------------------
Copyright (C) 1994,1995 by Andrey A. Chernov, Moscow, Russia. All rights reserved.
Copyright 1999,2000 by Jef Poskanzer <jef@acme.com>. All rights reserved.
Copyright (C) 1995 by Jef Poskanzer <jef@acme.com>. All rights reserved.
Copyright (C) 1995,2000 by Jef Poskanzer <jef@acme.com>. All rights reserved.