Geodesic
On the existence of non-negative bases in subgroups of free groups of Schreier varieties
Matematičeskie voprosy kriptografii, Tome 10 (2019), pp. 53-65

Voir la notice de l'article provenant de la source Math-Net.Ru

We show that a subgroup $H$ of a free group $F(X)$ has a non-negative (with respect to $X$) basis if and only if $H$ is generated by the set of all its non-negative (with respect to $X$) elements. A similar result is proved for subgroups of free Abelian groups. 
@article{MVK_2019_10_a3,
     author = {I. A. Kruglov and I. V. Cherednik},
     title = {On the existence of non-negative bases in subgroups of free groups of {Schreier} varieties},
     journal = {Matemati\v{c}eskie voprosy kriptografii},
     pages = {53--65},
     publisher = {mathdoc},
     volume = {10},
     year = {2019},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MVK_2019_10_a3/}
}
TY  - JOUR
AU  - I. A. Kruglov
AU  - I. V. Cherednik
TI  - On the existence of non-negative bases in subgroups of free groups of Schreier varieties
JO  - Matematičeskie voprosy kriptografii
PY  - 2019
SP  - 53
EP  - 65
VL  - 10
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/MVK_2019_10_a3/
LA  - ru
ID  - MVK_2019_10_a3
ER  - 
%0 Journal Article
%A I. A. Kruglov
%A I. V. Cherednik
%T On the existence of non-negative bases in subgroups of free groups of Schreier varieties
%J Matematičeskie voprosy kriptografii
%D 2019
%P 53-65
%V 10
%I mathdoc
%U http://geodesic.mathdoc.fr/item/MVK_2019_10_a3/
%G ru
%F MVK_2019_10_a3
I. A. Kruglov; I. V. Cherednik. On the existence of non-negative bases in subgroups of free groups of Schreier varieties. Matematičeskie voprosy kriptografii, Tome 10 (2019), pp. 53-65. http://geodesic.mathdoc.fr/item/MVK_2019_10_a3/