@article{HHA_2017_19_2_a12,
     author = {Talia Fern\'os and Alain Valette},
     title = {The {Mayer{\textendash}Vietoris} sequence for graphs of groups, property {(T),} and the first $\ell^2${-Betti} number},
     journal = {Homology, homotopy, and applications},
     pages = {251--274},
     publisher = {mathdoc},
     volume = {19},
     number = {2},
     year = {2017},
     doi = {10.4310/HHA.2017.v19.n2.a13},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4310/HHA.2017.v19.n2.a13/}
}