@article{TRSPY_2015_289_a11,
     author = {F. N. Pakhomov},
     title = {On elementary theories of ordinal notation systems based on reflection principles},
     journal = {Informatics and Automation},
     pages = {206--226},
     publisher = {mathdoc},
     volume = {289},
     year = {2015},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TRSPY_2015_289_a11/}
}