@article {BoClDu2010,
    author = {Bousquet-M\'{e}lou, Mireille and Claesson, Anders and Dukes, Mark
              and Kitaev, Sergey},
     title = {{$(2+2)$}-free posets, ascent sequences and pattern avoiding
              permutations},
   journal = {J. Combin. Theory Ser. A},
  fjournal = {Journal of Combinatorial Theory. Series A},
    volume = {117},
      year = {2010},
    number = {7},
     pages = {884--909},
      issn = {0097-3165},
       doi = {10.1016/j.jcta.2009.12.007},
       url = {https://doi.org/10.1016/j.jcta.2009.12.007},
}