@article{ZNSL_2012_402_a1,
     author = {D. S. Ananichev and M. V. Volkov and V. V. Gusev},
     title = {Primitive digraphs with large exponents and slowly synchronizing automata},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {9--39},
     year = {2012},
     volume = {402},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_2012_402_a1/}
}