1. Ch. Manolatou and M. Lipson, J. Lightwave Technol., 24, No. 3, 1433–1439 (2006).
2. R. R. Vardanyan, V. K. Dallakyan, and U. Kerst, Izv. NAS Armenia, 47, No. 2, 111–120 (2012).
3. T. Sameshima, H. Hayasaka, and T. Haba, Jpn. J. Appl. Phys., 48, 0212042 (2009).
4. R. A. Baltrameyunas, Yu. Yu. Vaitkus, and V. I. Gavryushin, Zh. Exp. Teor. Fiz., 87, Vyp. 1(7), 74–83 (1984).
5. V. S. Vavilov, Usp. Fiz. Nauk, 164, No. 3, 287–296 (1994).