A neutral network based identification for complex non-linear systemsVaarmann, OtuProceedings of the 3rd International Conference on Applied Operational Research, 24-26 August 2011, Istanbul, Turkey2011 / p. 39-46 Some approximate Gauss–Newton-type methods for nonlinear ill-posed problemsKangro, Inga; Kangro, Raul; Vaarmann, OtuProceedings of the Estonian Academy of Sciences2013 / p. 227-237 https://artiklid.elnet.ee/record=b2651797*est