@article{AIHPA_1979__31_3_173_0,
     author = {Koch, Hans},
     title = {Irreducible kernels and bound states in $\lambda \mathcal {P}(\varphi )_2$ models},
     journal = {Annales de l'institut Henri Poincar\'e. Section A, Physique Th\'eorique},
     pages = {173--234},
     publisher = {Gauthier-Villars},
     volume = {31},
     number = {3},
     year = {1979},
     language = {en},
     url = {http://www.numdam.org/item/AIHPA_1979__31_3_173_0/}
}