@article {feltrin2017,
	title = {An application of coincidence degree theory to cyclic feedback type systems associated with nonlinear differential operators},
	journal = {Topol. Methods Nonlinear Anal.},
	volume = {50},
	number = {2},
	year = {2017},
	pages = {683{\textendash}726},
	publisher = {Nicolaus Copernicus University, Juliusz P. Schauder Centre for Nonlinear Studies},
	doi = {10.12775/TMNA.2017.038},
	url = {https://doi.org/10.12775/TMNA.2017.038},
	author = {Guglielmo Feltrin and Fabio Zanolin}
}
