sqrt(5):2 Mode Interactions on a Square Lattice. - David M. Winterbottom (Int. J. Bifurc. Chaos, 2004)

Pattern Formation in a Model of a Vibrated Granular Layer. - David M. Winterbottom; S. M. Cox; P. C. Matthews (SIAM J. Appl. Dyn. Syst., 2008)