A snippet from their README file:
University of Manchester The NURBS Library Computer Graphics Unit Manchester Computing Centre David Yip & Terry Hewitt Non-Uniform Rational B-splines (NURBS) have been adopted by a number of international standards over recent years: PHIGS PLUS, STEP, CGM Addenda, and GKS Review. These groups have identified NURBS as the technology for curve and surface representation. The NURBS library is a collection of functions and routines to exploit this technology.
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