@article {326191,
	title = {Honeycomb phononic crystals with self-similar hierarchy},
	journal = {Physical Review B},
	volume = {92},
	year = {2015},
	pages = {104304},
	author = {Davood Mousanezhad and Sahab Babaee and Ranajay Ghosh and Elsadig Mahdi and Katia Bertoldi and Ashkan Vaziri}
}
