1. ANSI (1966) FORTRAN. ANS X3.9-1966. New York: American National Standards Institute.
2. ANSI (1974) COBOL. ANS X3.23-1974. New York: American National Standards Institute.
3. ANSI (1978) FORTRAN. ANS X3.9-1978. New York: American National Standards Institute.
4. Brown W.S. (1965), An Operating Environment for Dynamic Recursive Computer Programming Systems. Comm. ACM Vol. 8, pp. 371–377.
5. Dunn R.C. (1974), Design of a Higher-Level Language Transput system. Ph.D. Thesis, University of Colorado.