1. ►
http://www.pveducation.org/equations/photon-energy-ev
. Accessed 17 Feb 2011.
2. ►
https://www.rp-photonics.com/rare_earth_doped_gain_media.html
. Accessed 17 Feb 2011.
3. ►
https://www.rp-photonics.com/dye_lasers.html?s=ak
. Accessed 30 July 2016.
4. ►
http://www.laserdiodesource.com/
. Accessed 30 July 2016.
5. ►
http://www.olympusmicro.com/primer/java/lasers/diodelasers/index.html
. Accessed 30 July 2016.