@article{NSJOM_1993_23_1a_18,
     author = {Doroslova\v{c}ki Rade},
     title = {The set 

 of all the words of length n over any alphabet with the forbidden 

 subword aa{\textellipsis}a where the letter a is fixed},
     journal = {Novi Sad Journal of Mathematics},
     pages = {227-234},
     publisher = {mathdoc},
     volume = {23},
     number = {1},
     year = {1993},
     url = {http://geodesic.mathdoc.fr/item/NSJOM_1993_23_1a_18/}
}