Reference:

Antti Ukkonen, Kai Puolamäki, Aristides Gionis, and Heikki Mannila. A randomized approximation algorithm for computing bucket orders. Information Processing Letters, 109(7):356–359, 2009.

Suggested BibTeX entry:

@article{Ukkonen09ipl,
    author = {Antti Ukkonen and Kai Puolam\"aki and Aristides Gionis and Heikki Mannila},
    journal = {Information Processing Letters},
    number = {7},
    pages = {356--359},
    title = {A Randomized Approximation Algorithm for Computing Bucket Orders},
    volume = {109},
    year = {2009},
}