no. 3

Returns to the origin for a randomized random walk
Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 3, Tome 25 (1971) no. 3, pp. 389-395. 
@article{ASNSP_1971_3_25_3_389_0,
     author = {Gibson, A. E. and Conolly, B. W.},
     title = {Returns to the origin for a randomized random walk},
     journal = {Annali della Scuola Normale Superiore di Pisa - Classe di Scienze},
     pages = {389--395},
     publisher = {Scuola normale superiore},
     volume = {Ser. 3, 25},
     number = {3},
     year = {1971},
     zbl = {0234.60082},
     mrnumber = {319286},
     language = {en},
     url = {http://www.numdam.org/item/ASNSP_1971_3_25_3_389_0/}
}
Gibson, A. E.; Conolly, B. W. Returns to the origin for a randomized random walk. Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 3, Tome 25 (1971) no. 3, pp. 389-395. http://www.numdam.org/item/ASNSP_1971_3_25_3_389_0/

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