1. Jackson, P. H, U. S. Patent No. 357999 (1886/88).
2. Freyssinet, E., and Seailles, J., French Patent No. 680 547 (1928).
3. Magnel, G., Prestressed Concrete, 3rd Ed., revised and enlarged, Concrete Publications Ltd., London, 1954.
4. Guyon, Y., Prestressed Concrete, V. 1 and 2, John Wiley and Sons, New York, 1953, 1960. Also Limit State Design of Prestressed Concrete, translated from French, Halstead and Wiley, New York, 1972.
5. Abeles, P., An Introduction to Prestressed Concrete, V. 1 and 2, Concrete Publications Ltd., London, 1964.