1. A.J.B. Muwanguzi, A.V. Karasev, J.K. Byaruhanga, P.G. Jönssonnsson, ISRN Materials Science, 2012 (2012) 9.
2. W.S. Association, in, Brussels, Belgium, (2014).
3. V. Mironovs, J. Broņka, A. Korjakins, J. Kazjonovs, in: 3rd International Conference CIVIL ENGINEERING`11 2011, pp.13-19.
4. R.J. Parker, Advances in Permanent Magnet, John Wiley & Sons, USA, (1990).
5. D.P. Bhandarkar, IEEE Transactions on Computers, 24, 1125-1129.