TY  - JOUR
AU  - Širáň, Jozef
TI  - Coverings of graphs and maps, orthogonality, and eigenvectors
JO  - Journal of Algebraic Combinatorics
PY  - 2001
SP  - 57
EP  - 72
VL  - 14
IS  - 1
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/JAC_2001__14_1_a1/
LA  - en
ID  - JAC_2001__14_1_a1
ER  -