(from the docuentation, apparently extracted from the dos version of isetl, also note the apparent lack of interest past 1990... maybe irrelevent, the interpreter works)
ISETL Copyright Information --------------------------- Copyright 1987, 1988, 1989, 1990 Gary Levin This manual and the accompanying software may be freely copied, subject to the restriction that it not be sold for profit. (This would permit bulk copying and sale at cost.) The software is offered as-is, but we will attempt to correct errors in our code. Portions of the manual and and the accompanying software are derived from the Interactive Line Editor which was released with the following copyright restrictions. Copyright 1988 Evans and Sutherland Computer Corporation Salt Lake City, Utah All rights reserved. THE INFORMATION IN THIS SOFTWARE IS SUBJECT TO CHANGE WITHOUT NOTICE AND SHOULD NOT BE CONSTRUED AS A COMMITMENT BY EVANS & SUTHERLAND. EVANS & SUTHERLAND MAKE NO REPRESENTATIONS ABOUT THE SUITABILITY OF THIS SOFTWARE FOR ANY PURPOSE. IT IS SUPPLIED "AS IS" WITHOUT EXPRESS OR IMPLIED WARRANTY. IF THE SOFTWARE IS MODIFIED IN A MANNER CREATING DERIVATIVE COPYRIGHT RIGHTS, APPROPRIATE LEGENDS MAY BE PLACED ON THE DERIVATIVE WORK INADDITION TO THAT SET FORTH ABOVE. Permission to use, copy, modify, and distribute this software and its documentation for any purpose and without fee is hereby granted, provided that the above copyright notice appear in all copies and that bothe the copyright notice and this permission notice appear in supporting documentation, and thet the name of Evans & Sutherland not be used in advertising or publicly pertaining to distribution of the software without specific, written prior permission. Written by: Robert C. Pendleton, Evans & Sutherland, Interactive Systems Division, Salt Lake City, Utah. Modified for ISETL bu Gary Levin.