@article{articleccbd5ae0,
title   = {X-Ray AGB Stars in the 4XMM-DR9 Catalog: Further Evidence for Companions},
author = {Ortiz, Roberto Pereira and Guerrero, Martín A},
year = {2021},
doi = {10.3847/1538-4357/abefd7},
journal   = {The Astrophysical Journal}
}