@article{10_4064_sm206_1_6,
     author = {Mikhail Lifshits and Werner Linde},
     title = {Compactness properties of weighted summation operators on trees{\textemdash}the critical case},
     journal = {Studia Mathematica},
     pages = {75--96},
     year = {2011},
     volume = {206},
     number = {1},
     doi = {10.4064/sm206-1-6},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/sm206-1-6/}
}