@article{ITA_1991__25_2_125_0,
     author = {Heuter, Uschi},
     title = {First-order properties of trees, star-free expressions, and aperiodicity},
     journal = {RAIRO - Theoretical Informatics and Applications - Informatique Th\'eorique et Applications},
     pages = {125--145},
     publisher = {EDP-Sciences},
     volume = {25},
     number = {2},
     year = {1991},
     mrnumber = {1110980},
     zbl = {0741.68065},
     language = {en},
     url = {http://www.numdam.org/item/ITA_1991__25_2_125_0/}
}