@article{10_37236_2441,
     author = {Andreas Distler and J. D. Mitchell},
     title = {The number of nilpotent semigroups of degree 3.},
     journal = {The electronic journal of combinatorics},
     year = {2012},
     volume = {19},
     number = {2},
     doi = {10.37236/2441},
     zbl = {1254.20049},
     url = {http://geodesic.mathdoc.fr/articles/10.37236/2441/}
}