@article{Moza2022, 
author = {Gheorghe Moza and Mihaela Sterpu and Carmen Rocşoreanu},
title = {An analysis of two degenerate double-Hopf bifurcations},
year = {2022},
journal = {Electronic Research Archive},
volume = {30},
number = {1},
pages = {382-403},
keywords = {asymptotic analysis, double Hopf bifurcation, degenerate double Hopf bifurcation, bifurcation diagrams, normal forms},
url = {https://www.sciopen.com/article/10.3934/era.2022020},
doi = {10.3934/era.2022020},
abstract = {The generic double-Hopf bifurcation is presented in detail in literature in textbooks like references. In this paper we complete the study of the double-Hopf bifurcation with two degenerate (or nongeneric) cases. In each case one of the generic conditions is not satisfied. The normal form and the corresponding bifurcation diagrams in each case are obtained. New possibilities of behavior which do not appear in the generic case were found.}
}