TY - JOUR AU - Zelinka, Bohdan TI - The 3-path-step operator on trees and unicyclic graphs JO - Mathematica Bohemica PY - 2002 SP - 33 EP - 40 VL - 127 IS - 1 PB - mathdoc UR - http://geodesic.mathdoc.fr/articles/10.21136/MB.2002.133982/ DO - 10.21136/MB.2002.133982 LA - en ID - 10_21136_MB_2002_133982 ER -