On interval enclosures using slope arithmetic

This paper describes how a combination of interval derivative arithmetic and interval slope arithmetic can be used with the programming language Pascal-SC to obtain an enclosure of the range of a factorable function @?:R^n -> R^1 with @? @? C^2 (D) which is often narrower than that which is obtained by using slope arithmetic alone and which is always narrower than that which is obtained by using interval derivative arithmetic alone.