@conference {,
	title = {Indoor Positioning in Large Environments: Ultrasonic and UWB Technologies},
	booktitle = {International Conference on Indoor Positioning and Indoor Navigation },
	year = {2019},
	month = {10/2019},
	pages = {1-8},
	publisher = {IPIN},
	organization = {IPIN},
	address = {Pisa, Italia},
	isbn = {978-1-7281-1788-1},
	author = {Gualda, D and A. Hernandez and J. M. Villadangos and Ure{\~n}a, J. and Jimenez, A. and F. Seco}
}
