Cliff Reiter, With APL & J: Adaptive Integration: Operators and Adverbs Come of Age, APL Quote Quad, 32 3 (2002) 26-30

Implementation of adaptive integration in APL2 and J using operators and adverbs is discussed. We see that these give efficient ways to implement the algorithms while utilizing the flexibility of function arguments.

See also: Book with original implementation: C. Reiter and W. Jones, APL with a Mathematical Accent, Brooks-Cole Publishing Co., Pacific Grove (1990) [abstract]