Geodesic
A Property of Fibonacci words
Séminaire lotharingien de combinatoire, Tome 05 (1981) 
Aldo de Luca. A Property of Fibonacci words. Séminaire lotharingien de combinatoire, Tome 05 (1981). http://geodesic.mathdoc.fr/item/SLC_1981_05_a7/
@article{SLC_1981_05_a7,
     author = {Aldo de Luca},
     title = {A {Property} of {Fibonacci} words},
     journal = {S\'eminaire lotharingien de combinatoire},
     year = {1981},
     volume = {05},
     url = {http://geodesic.mathdoc.fr/item/SLC_1981_05_a7/}
}
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AU  - Aldo de Luca
TI  - A Property of Fibonacci words
JO  - Séminaire lotharingien de combinatoire
PY  - 1981
VL  - 05
UR  - http://geodesic.mathdoc.fr/item/SLC_1981_05_a7/
ID  - SLC_1981_05_a7
ER  - 
%0 Journal Article
%A Aldo de Luca
%T A Property of Fibonacci words
%J Séminaire lotharingien de combinatoire
%D 1981
%V 05
%U http://geodesic.mathdoc.fr/item/SLC_1981_05_a7/
%F SLC_1981_05_a7

Voir la notice de l'acte provenant de la source Séminaire Lotharingien de Combinatoire website

By making use of a result of J. Berstel (unpublished) which states that, for n>=3, fn has a palindrome left factor of length |fn|-2, we prove that for all n>=4, fn is the product of two uniquely determined palindrome words, of lengths |fn-1|-2 and |fn-2|+2. It follows that for n>4 the sequence {fn} is the unique sequence of words satisfying the previously mentioned properties and the additional requirements that the words contain at least two different letters and that all begin with the same letter (namely, b).

The paper has been finally published under the title "A combinatorial property of the Fibonacci words" in Inform. Process. Lett. 12 (1981), 193-195.