@article{AIHPA_1971__15_1_69_0,
     author = {Vu Thanh Khi\^et},
     title = {On the instability in universe},
     journal = {Annales de l'institut Henri Poincar\'e. Section A, Physique Th\'eorique},
     pages = {69--89},
     publisher = {Gauthier-Villars},
     volume = {15},
     number = {1},
     year = {1971},
     language = {en},
     url = {http://archive.numdam.org/item/AIHPA_1971__15_1_69_0/}
}