[1] Prasad, P.N. and Williams, D.J. (1991) Introduction to Nonlinear Optical Effects in Molecules and Polymers. John Wiley & Sons, New York.
[2] Munn, R.W. and Ironside, C.N. (1993) Principles and Applications of Nonlinear Optical Materials. Chapman and Hall, London. http://dx.doi.org/10.1007/978-94-011-2158-3
[3] Bardan, J., Hierle, R., Perigaud, A., Zyss, J. and Williams, D.J. (1993) Nonlinear Optical Properties of Organic Molecules and Polymeric Materials, Vol. 223 of ACS Series. American Chemical Society, Washington.
[4] Xu, R.J. (2010) 4-Methoxyanilinium Iodide. Acta Crystallographica E, 66, Article ID: o1794.
[5] Gupta, V. and Mansingh, A. (1996) Influence of Post Deposition Annealing on the Structural and Optical Properties of Sputtered Zinc Oxide Film. Journal of Applied Physics, 80, 1063-1073.
http://dx.doi.org/10.1063/1.362842
[6] Gaffar, M.A., Abu El-Fadl, A. and Bin Anooz, S., (2003) Influence of Strontium Doping on the Indirect Band Gap and Optical Constants of Ammonium Zinc Chloride Crystals. Physica B, 327, 43-54.
http://dx.doi.org/10.1016/S0921-4526(02)01700-3
[7] Taber, D. (1951) The Hardness of Materials. Clarendon Press, Oxford.
[8] Pethica, J.B. and Taber, D. (1979) Contact of Characterized Metal Surface at Very Low Loads: Deformation and Adhesion. Surface Science, 89, 182-190.
http://dx.doi.org/10.1016/0039-6028(79)90606-X
[9] Smith, R.L. and Sandland, G.E. (1923) An Accurate Method of Determining the Hardness of Metals with Reference to those of a High Degree of Hardness. Proceedings of the Institution of Mechanical Engineers, 1, 623-641.
[10] Batta Calleja, F.J., Rueda, D.R., Poster, R.S. and Mead, W.T. (1980) New Aspects of the Microhardness of Ultra Oriented Polyethiline. J. Master Science, 15, 762-765.
[11] Matthias, B.T. and Remeika, J.P. (1951) Dielectric Properties of Sodium and Potassium Niobate. Physical Review, 82, 727-729. http://dx.doi.org/10.1103/PhysRev.82.727
[12] Triebwasser, S. (1959) Study of Ferroelectric Transitions of Solid-Solution Single Crystals of KNbO3-KTaO3. Physical Review, 114, 63-70. http://dx.doi.org/10.1103/PhysRev.114.63
[13] Govinda, S. and Rao, K.V. (1975) Dielectric Properties of Single Crystals of Al2O3 and Al2O3 Doped with Chromium and Vanadium. Physica Status Solidi (A), 27, 639-644.
http://dx.doi.org/10.1002/pssa.2210270237
[14] Smyth, C.P. (1965) Dielectric Behavior and Structure. McGraw-Hill, New York.
[15] Balarew, C. and Duhlew, R. (1984) Application of the Hard and Soft Acids and Bases Concept to Explain Ligand Coordination in Double Salt Structures. Journal of Solid State Chemistry, 55, 1-6.
http://dx.doi.org/10.1016/0022-4596(84)90240-8