'A'
G. B. Perez, I. H. Cuatecatl, and J. C. Mixcoatl, "Multiwavelength erbium-doped fiber ring laser thermally-tunable," Frontiers in Optics 2006, Rochester, NY, USA, Oc. 2006, paper JWD134.
Authors' address:
Benemerita Universidad Automa de Puebla, Mexico

'B'
Y. W. Lee and B. Lee, "Wavelength-switchable erbium-doped fiber ring laser using spectral polarization-dependent loss element," IEEE Photonics Technology Letters, vol. 15, no. 6, pp. 795-797, 2003.