@article{DMTCS_2009_special_256_a10,
     author = {Kitaev, Sergey and Liese, Jeffrey and Remmel, Jeffrey and Sagan, Bruce},
     title = {Rationality, irrationality, and {Wilf} equivalence in generalized factor order},
     journal = {Discrete mathematics & theoretical computer science},
     publisher = {mathdoc},
     volume = {DMTCS Proceedings vol. AK, 21st International Conference on Formal Power Series and Algebraic Combinatorics (FPSAC 2009)},
     year = {2009},
     doi = {10.46298/dmtcs.2688},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.46298/dmtcs.2688/}
}