Calvin C. Elgot: Erratum and Corrigendum for "Structured Programming With and Without GO TO Statments".
232, (see: TSE 2(1): 41-54 (1976))
Volume 2, Number 4, December 1976
David Gries: An Illustration of Current Ideas on the Derivation of Correctness Proofs and Correct Programs.
238-244, (correction: TSE 3(3): 262 (1977))