, Within the main text, references should be designated by a number in brackets [1], and they should be followed by a comma or

G. I. Stegeman and R. H. Stolen, Waveguides and fibers for nonlinear optics, J. Opt. Soc. Am. B, vol.6, pp.652-662, 1989.

F. Charra, F. Kajzar, J. M. Nunzi, P. Raimond, and E. Idiart, Light-induced second-harmonic generation in azo-dye polymers, Opt. Lett, vol.18, pp.941-943, 1993.

C. Fiorini, F. Charra, P. Raimond, A. Lorin, and J. M. Nunzi, All-optical induction of noncentrosymmetry in a transparent nonlinear polymer rod, Opt. Lett, vol.22, pp.1846-1848, 1997.

R. Author, A. Barille, B. Samoc, M. Luther-davies, J. M. Samoc et al., Self-reconstructing all-optical poling in polymer fibers, Opt. Lett, vol.38, issue.16, pp.2945-2948, 2013.