 Sontag, E. 

 Sontag, E. (C. Darken, M. Donahue, L. Gurvits and E. Sontag)  Rate of approximation results motivated by robust neural network learning  1993 
 Sontag, E. (B. DasGupta, H. T. Siegelmann and E. Sontag)  On a learnability question associated to neural networks with continuous activations  1994 
 Sontag, E. (B. DasGupta, H. T. Siegelmann and E. Sontag)  On the complexity of training neural networks with continuous activation functions  1995 
