Non Standard Finite Difference Scheme for Mutualistic Interaction   Description
  One of the more interesting themes of the mathematical ecology is the description of the mutualistic interaction between two interacting species. Based on continuous-time model developed by Holland and DeAngelis 2009 for consumer-resource mutualism description, this work deals with the application of the Mickens Non Standard Finite Difference method to transform the continuous-time scheme into a discrete-time one. It has been proved that the Mickens scheme is dynamically consistent with the original one regardless of the step-sizes used in numerical simulations, in opposition of the forward Euler method that shows numerical instabilities when the step size overcomes a critical value. 
Gianluca Gabbriellini
q-bio.PE nlin.AO