@article{AA_1996_8_1_a8,
     author = {B. Helffer},
     title = {Correlation decay and gap of the transfer operator},
     journal = {Algebra i analiz},
     pages = {192--210},
     publisher = {mathdoc},
     volume = {8},
     number = {1},
     year = {1996},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/AA_1996_8_1_a8/}
}