Parameter estimates for fractional autoregressive spatial processes
  A binomial-type operator on a stationary Gaussian process is introduced in order to model long memory in the spatial context. Consistent estimators of model parameters are demonstrated. In particular, it is shown that $\hat{d}_N-d=O_P(\frac{(\operatorname {Log}N)^3}{N})$, where $d=(d_1,d_2)$ denotes the long memory parameter. 
Y. Boissy, B. B. Bhattacharyya, X. Li, G. D. Richardson