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4. D. D. Arnaudov, ?On some characteristic features of ALGOL-68 and its connection with ALGOL-60,? in: Tsifr. Vychisl. Tekh. Programmir., No. 5, Sov. Radio, Moscow (1969), pp. 119?122.
5. A. N. Baluev and I. L. Bratchikov, ?Some special features of an intermediate translator language with ALGOL-68,? in: Teoriya Yazykov i Metody Postroeniya Sistem Programmir., Kiev-Alushta (1971), pp. 391?396.