@article{ITA_1999__33_3_213_0,
     author = {Phan Trung Huy and Nguyen Huong Lam},
     title = {Unavoidable set : extension and reduction},
     journal = {RAIRO - Theoretical Informatics and Applications - Informatique Th\'eorique et Applications},
     pages = {213--225},
     publisher = {EDP-Sciences},
     volume = {33},
     number = {3},
     year = {1999},
     mrnumber = {1728424},
     zbl = {0941.68104},
     language = {en},
     url = {http://archive.numdam.org/item/ITA_1999__33_3_213_0/}
}