@article {garrione2012,
	title = {Resonance at the first eigenvalue for first-order systems in the plane: vanishing Hamiltonians and the Landesman-Lazer condition},
	journal = {Differential Integral Equations},
	volume = {25},
	number = {5/6},
	year = {2012},
	month = {05},
	pages = {505{\textendash}526},
	publisher = {Khayyam Publishing, Inc.},
	url = {https://projecteuclid.org:443/euclid.die/1356012676},
	author = {Maurizio Garrione}
}
