1. (ASL) ["Structured AlgeBraic Specifications: A Kernel Language", M. Wirsing, Theor Comput Sci 42, pp.123-249, Elsevier 1986]. 2. (ASF) A language for equational specification of aBstract data types. ["AlgeBraic Specification", J.A. Bergstra et al, A-W 1989]. (1995-12-13)