@article{1077311639,
author = {Ocken, Stanley},
title = {The commutativity of tunnel sum},
journal = {Duke Math. J.},
volume = {43},
number = {1},
year = {1976},
pages = { 285-294},
language = {en},
url = {http://dml.mathdoc.fr/item/1077311639}
}
Ocken, Stanley. The commutativity of tunnel sum. Duke Math. J., Tome 43 (1976) no. 1, pp. 285-294. http://gdmltest.u-ga.fr/item/1077311639/