@article{10_4064_aa_26_1_47_57,
     author = {Tonko Tonkov},
     title = {On the average length of finite continued fractions},
     journal = {Acta Arithmetica},
     pages = {47--57},
     publisher = {mathdoc},
     volume = {26},
     number = {1},
     year = {1974},
     doi = {10.4064/aa-26-1-47-57},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/aa-26-1-47-57/}
}