@article{10_4153_CJM_2007_035_1,
     author = {Ortner, Ronald and Woess, Wolfgang},
     title = {Non-Backtracking {Random} {Walks} and {Cogrowth} of {Graphs}},
     journal = {Canadian journal of mathematics},
     pages = {828--844},
     year = {2007},
     volume = {59},
     number = {4},
     doi = {10.4153/CJM-2007-035-1},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-2007-035-1/}
}