Dominguez-Garcia, J.L.; Rogers, D.J.; Ugalde-Loo, C.E.; Liang, J.; Gomis-Bellmunt, O. "Effect of non-standard operating frequencies on the economic cost of offshore AC networks" Renewable Energy 44, pp. 267 - 280. 2012 DOI: 10.1016/j.renene.2012.01.093