TY  - RPRT
TI  - Spectral gaps for electromagnetic and scalar waves: Possible explanation for certain differences.
AU  - MM Sigalas
AU  - EN Economou
AU  - M Kafesaki
PY  - 1994
DO  - 10.1103/physrevb.50.3393
UR  - https://pubmed.ncbi.nlm.nih.gov/9976594/
ID  - 9976594
ER  -