@article {2007_3,
	title = {Structural interfaces in linear elasticity. Part I: Nonlocality and gradient approximations},
	journal = {Journal of the Mechanics and Physics of Solids},
	volume = {55},
	year = {2007},
	pages = {1-34},
	author = {Bertoldi, K. and Bigoni, D. and Drugan, W.J.}
}
