@article{10_37236_2018,
     author = {Alessandro De Luca and Christophe Reutenauer},
     title = {Christoffel words and the {Calkin-Wilf} tree},
     journal = {The electronic journal of combinatorics},
     year = {2011},
     volume = {18},
     number = {2},
     doi = {10.37236/2018},
     zbl = {1229.68061},
     url = {http://geodesic.mathdoc.fr/articles/10.37236/2018/}
}