@article{10_4064_aa_78_3_227_239,
     author = {Lorenz Halbeisen and Norbert Hungerb\"uhler},
     title = {Optimal bounds for the length of rational {Collatz} cycles},
     journal = {Acta Arithmetica},
     pages = {227--239},
     publisher = {mathdoc},
     volume = {78},
     number = {3},
     year = {1996},
     doi = {10.4064/aa-78-3-227-239},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/aa-78-3-227-239/}
}