@article{PDML_1977__14_4_57_0,
     author = {Richard, Denis},
     title = {On {External} {Properties} of {Nonstandard} {Models} of {Arithmetic}},
     journal = {Publications du D\'epartement de math\'ematiques (Lyon)},
     pages = {57--75},
     publisher = {Universit\'e Claude Bernard - Lyon 1},
     volume = {14},
     number = {4},
     year = {1977},
     mrnumber = {520991},
     zbl = {0405.03036},
     language = {en},
     url = {http://archive.numdam.org/item/PDML_1977__14_4_57_0/}
}