Most of these files were obtained (as of 2001-12-09) from http://www.pa.msu.edu/ftp/pub/unix/cd1.3.tar.gz This software was written originally by G. Edward Johnson at NIST, but it is no longer maintained by him. It is public-domain software except for the small part licensed under the libgd license (see his documentation). The PLplot developer's contribution is CMakeLists.txt, cddll.h, and some small visibility modifications to cd.h. We call the resulting library, libnistcd to distinguish it from all the other "libcd" libraries out there.