Naish, Lee "Adding equations to NU-Prolog"

Maluszynski, Jan and Martin Wirsing, editors, Proc (1991) Maluszynski, Jan and Martin Wirsing, editors, Proceedings of the 3rd International Symposium on Programming Language Implementation and Logic Programming (Passau, Germany), pages 255-274. Springer­Verlag, LNCS 528 (August 1991).  

Languages mentioned NUE-Prolog {1991}