@article{MR0807900,
title = {{Degenerate Hopf bifurcation and nerve impulse}},
author = {IS Labouriau},
doi = {10.1137/0516083},
issn = {0036-1410},
journal = {SIAM Journal on Mathematical Analysis},
number = {6},
pages = {1121-1133},
publisher = {SIAM},
volume = {16},
year = {1985}
}