@article{AIHPA_1979__31_1_1_0, author = {Demoen, Bart}, title = {Coherent and quasi-free states}, journal = {Annales de l'institut Henri Poincar\'e. Section A, Physique Th\'eorique}, pages = {1--4}, publisher = {Gauthier-Villars}, volume = {31}, number = {1}, year = {1979}, mrnumber = {557048}, zbl = {0434.46043}, language = {en}, url = {http://archive.numdam.org/item/AIHPA_1979__31_1_1_0/} }
Demoen, Bart. Coherent and quasi-free states. Annales de l'institut Henri Poincaré. Section A, Physique Théorique, Volume 31 (1979) no. 1, pp. 1-4. http://archive.numdam.org/item/AIHPA_1979__31_1_1_0/