@article{MZM_1984_36_4_a11,
     author = {V. N. Krivtsov},
     title = {A formal system of negationless arithmetic that is conservative with respect to heyting arithmetic},
     journal = {Matemati\v{c}eskie zametki},
     pages = {583--592},
     publisher = {mathdoc},
     volume = {36},
     number = {4},
     year = {1984},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1984_36_4_a11/}
}