@article{1183742382,
author = {Buechler, Steven},
title = {On Nontrivial Types of $U$-Rank},
journal = {J. Symbolic Logic},
volume = {52},
number = {1},
year = {1987},
pages = { 548-551},
language = {en},
url = {http://dml.mathdoc.fr/item/1183742382}
}
Buechler, Steven. On Nontrivial Types of $U$-Rank. J. Symbolic Logic, Tome 52 (1987) no. 1, pp. 548-551. http://gdmltest.u-ga.fr/item/1183742382/