2) P. M. Castle and R. K. Sadhir : Potential Application of Lasers in Photocuring, Photomodification, and Photocrosslinking of Polymers, in Lasers in Polymer Science and Technology : Applications, Vol. III. J.P. Fouassier ed., chapt. 2, CRC Press, Inc., Boca Raton, Florida. (1990) 37.