@article{10_37236_329,
     author = {Lily L. Liu},
     title = {Positivity of three-term recurrence sequences},
     journal = {The electronic journal of combinatorics},
     year = {2010},
     volume = {17},
     doi = {10.37236/329},
     zbl = {1219.11022},
     url = {http://geodesic.mathdoc.fr/articles/10.37236/329/}
}