@Article{aron:50,
  author =       {N. Aronszajn},
  title =        {Theory of reproducing kernels},
  journal =      {Trans. American Mathematical Soc.},
  year =         {1950},
  volume =       {68},
  number =       {},
  pages =        {337--404}}


@Book{boch:55,
  author =       {S. Bochner},
  title =        {Harmonic Analysis and the Theory of Probability},
  publisher =    {University of California Press},
  year =         {1955},
  address =      {Los Angeles, California}}

@Book{broda:91,
  author =       {P. J. Brockwell and R. A. Davis},
  title =        {Time Series: Theory and Methods},
  publisher =    {Springer},
  year =         {1991},
  address =      {New York}}

@Article{christa:84,
  author =       {G. Christakos},
  title =        {On the problem of permissible covariance and variogram models},
  journal =      {Water Resources Research},
  year =         {1984},
  volume =       {20},
  number =       {2},
  pages =        {251--265}}

@Book{christa:00,
  author =       {G. Christakos},
  title =        {Modern Spatiotemporal Geostatistics},
  publisher =    {Oxford University Press},
  year =         {2000},
  address =      {New York}}

@Article{chripapa:00,
  author =       {G. Christakos and V. Papanicolaou},
  title =        {Norm-dependent covariance permissibility of weakly homogeneous spatial random fields and its consequences in spatial statistics},
  journal =      {Stochastic Environmental Research and Risk assessment},
  year =         {2000},
  volume =       {14},
  number =       {6},
  pages =        {471--478}}

@Book{crisha:00,
  author =       {N. Cristianini and J. Shawe-Taylor},
  title =        {An Introduction to Support Vector Machines and other Kernel-based Learning Methods},
  publisher =    {Cambridge University Press},
  year =         {2000},
  address =      {Cambridge}}

@Book{cressie:93,
  author =       {N. Cressie},
  title =        {Statistics for Spatial Data},
  publisher =    {John Wiley \& Sons},
  year =         {1993},
  address =      {New York}}

@Article{creshuang:99,
  author =       {N. Cressie and H.-C. Huang},
  title =        {Classes of nonseparable, spatio-temporal stationary covariance functions},
  journal =      {Journal of the American Statistical Association},
  year =         {1999},
  volume =       {94},
  number =       {448},
  pages =        {1330--1340}}

@Article{genper:01,
  author =       {M. G. Genton and O. Perrin},
  title =        {On a time deformation reducing nonstationary stochastic processes to local stationarity},
  journal =      {Technical Report NCSU},
  year =         {2001},
  volume =       {},
  number =       {},
  pages =        {}}

@Article{gilb:92,
  author =       {J. R. Gilbert and C. Moler and R. Schreiber},
  title =        {Sparse matrices in {MATLAB}: design and implementation},
  journal =      {SIAM Journal on Matrix Analysis},
  year =         {1992},
  volume =       {13},
  number =       {1},
  pages =        {333--356}}

@Article{gneit:02,
  author =       {T. Gneiting},
  title =        {Compactly supported correlation functions},
  journal =      {Journal of Multivariate Analysis},
  year =         {2002},
  volume =       {to appear},
  number =       {},
  pages =        {}}

@Article{gneit:01,
  author =       {T. Gneiting},
  title =        {Nonseparable, stationary covariance functions for space-time data},
  journal =      {Journal of the American Statistical Association},
  year =         {2002},
  volume =       {to appear},
  number =       {},
  pages =        {}}

@Book{graham:81,
  author =       {A. Graham},
  title =        {Kronecker Products and Matrix Calculus: with Applications},
  publisher =    {Ellis Horwood Limited},
  year =         {1981},
  address =      {New York}}


@Article{loeve:46,
  author =       {M. Lo\`eve},
  title =        {Fonctions al\'eatoires \`a d\'ecomposition orthogonale exponentielle},
  journal =      {La Revue Scientifique},
  year =         {1946},
  volume =       {84},
  number =       {},
  pages =        {159-162}}

@Book{loeve:48,
  author =       {M. Lo\`eve},
  title =        {Fonctions al\'eatoires du second ordre},
  publisher =    {In: Processus Stochastiques et Mouvement Brownien (P. L\'evy), Gauthier-Villars},
  year =         {1948},
  address =      {Paris}}

@Article{mandel:68,
  author =       {B. B. Mandelbrot and J. W. {Van~Ness}},
  title =        {Fractional Brownian motions, fractional noises and applications},
  journal =      {SIAM Review},
  year =         {1968},
  volume =       {10},
  number =       {},
  pages =        {422--437}}

@Book{matern:60,
  author =       {B. Mat\'ern},
  title =        {Spatial Variation},
  publisher =    {Springer},
  year =         {1960},
  address =      {New York}}

@Article{matheron:73,
  author =       {G. Matheron},
  title =        {The intrinsic random functions and their applications},
  journal =      {J. Appl. Probab.},
  year =         {1973},
  volume =       {5},
  number =       {},
  pages =        {439--468}}


@Article{mercer:09,
  author =       {J. Mercer},
  title =        {Functions of positive and negative type and their connection with the theory of integral equations},
  journal =      {Philos. Trans. Roy. Soc. London},
  year =         {1909},
  volume =       {A 209},
  number =       {},
  pages =        {415--446}}


@Article{perrin:99,
  author =       {O. Perrin and R. Senoussi},
  title =        {Reducing non-stationary stochastic processes to stationarity by a time deformation},
  journal =      {Statistics and Probability Letters},
  year =         {1999},
  volume =       {43},
  number =       {4},
  pages =        {393--397}}

@Article{perrin:00,
  author =       {O. Perrin and R. Senoussi},
  title =        {Reducing non-stationary random fields to stationarity and isotropy using a space deformation},
  journal =      {Statistics and Probability Letters},
  year =         {2000},
  volume =       {48},
  number =       {1},
  pages =        {23--32}}

@Article{sampson:92,
  author =       {P. D. Sampson and P. Guttorp},
  title =        {Nonparametric estimation of nonstationary spatial covariance structure},
  journal =      {Journal of the American Statistical Association},
  year =         {1992},
  volume =       {87},
  number =       {417},
  pages =        {108--119}}

@Article{schoenberg:38,
  author =       {I. J. Schoenberg},
  title =        { Metric spaces and completely monotone functions},
  journal =      {Annals of Mathematics},
  year =         {1938},
  volume =       {39},
  number =       {3},
  pages =        {811-841}}

@Article{silverman:57,
  author =       {R. A. Silverman},
  title =        {Locally stationary random processes},
  journal =      {IRE Transactions Information Theory},
  year =         {1957},
  volume =       {3},
  number =       {},
  pages =        {182--187}}

@Article{silverman:59,
  author =       {R. A. Silverman},
  title =        {A matching theorem for locally stationary random processes},
  journal =      {Communications on Pure and Applied Mathematics},
  year =         {1959},
  volume =       {12},
  number =       {},
  pages =        {373--383}}


@Book{stein:99,
  author =       {M. Stein},
  title =        {Interpolation of Spatial Data: Some Theory for Kriging},
  publisher =    {Springer},
  year =         {1999},
  address =      {New York}}


@Book{vapnik:95,
  author =       {V. Vapnik},
  title =        {The Nature of Statistical Learning Theory},
  publisher =    {Springer},
  year =         {1995},
  address =      {New York}}


@Book{vapnik:98,
  author =       {V. Vapnik},
  title =        {Statistical Learning Theory},
  publisher =    {Wiley},
  year =         {1998},
  address =      {New York}}


@Article{yaglom:57,
  author =       {A. M. Yaglom},
  title =        {Some classes of random fields in $n$-dimensional space, related to stationary random processes},
  journal =      {Theory of Probability and its Applications},
  year =         {1957},
  volume =       {2},
  number =       {},
  pages =        {273--320}}

@Book{yaglom:87,
  author =       {A. M. Yaglom},
  title =        {Correlation Theory of Stationary and Related Random Functions, Vol. I \& II},
  publisher =    {Springer Series in Statistics},
  year =         {1987},
  address =      {New York}}