@article{10_4153_CJM_1987_066_4,
     author = {Holladay, Kenneth},
     title = {Estimating the {Size} of {Context-Free} {Tiling} {Languages}},
     journal = {Canadian journal of mathematics},
     pages = {1413--1433},
     year = {1987},
     volume = {39},
     number = {6},
     doi = {10.4153/CJM-1987-066-4},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1987-066-4/}
}