1- http://onlinelibrary.wiley.com/doi/10.1002/cssc.201300986/full http://onlinelibrary.wiley.com/doi/10.1002/cssc.201300986/full
2- http://onlinelibrary.wiley.com/doi/10.1002/anie.201006639/full http://onlinelibrary.wiley.com/doi/10.1002/anie.201006639/full
3-http://onlinelibrary.wiley.com/doi/10.1002/er.3690/full
4- http://www.sciencedirect.com/science/article/pii/S0008622313006015
5-https://www.youtube.com/watch?v=8lTfYLuAeFU https://www.youtube.com/watch?v=8lTfYLuAeFU
6-https://www.youtube.com/watch?v=EYPapE-3FRw https://www.youtube.com/watch?v=EYPapE-3FRw