@article{10_37236_4459,
     author = {L. Bruce Richmond and Jeffrey O Shallit},
     title = {Counting the palstars},
     journal = {The electronic journal of combinatorics},
     year = {2014},
     volume = {21},
     number = {3},
     doi = {10.37236/4459},
     zbl = {1300.05017},
     url = {http://geodesic.mathdoc.fr/articles/10.37236/4459/}
}