@article{CMH_1993__68_2_140313,
     author = {T. Adachi and T. Sunada},
     title = {Density of states in spectral geometry.},
     journal = {Commentarii mathematici Helvetici},
     pages = {480--493},
     publisher = {mathdoc},
     volume = {68},
     number = {2},
     year = {1993},
     zbl = {0787.58042},
     url = {http://geodesic.mathdoc.fr/item/CMH_1993__68_2_140313/}
}