“…As underlined before, such a trace result has potential applications to inverse problem. Similar questions at a discrete level or on higher-dimensional domains are also considered, let us quote discrete laplacian on infinite networks [11,13,15,18,[20][21][22][23], two-dimensional domains with a fractal boundary [1][2][3][4], pre-fractal domains approximating the Koch snowflake [10]. Let us finally mention some related problems such as the Hamilton-Jacobi equation [5] and the Gauss-Bonnet operator on infinite graphs [6].…”