@article{MS2_1958__6_165695,
     author = {R.L. Goodstein},
     title = {Models of {Propositional} {Calculi} in {Recursive} {Arithmetic.}},
     journal = {Mathematica Scandinavica},
     pages = {293--296},
     publisher = {mathdoc},
     volume = {6},
     year = {1958},
     zbl = {0088.01001},
     url = {http://geodesic.mathdoc.fr/item/MS2_1958__6_165695/}
}