@conference {,
	title = {Robustness Study of a Multiple Ultrasonic Indoor Location System},
	booktitle = {Sixth International Conference on Indoor Positioning and Indoor Navigation (IPIN 2015)},
	year = {2015},
	month = {10/2015},
	pages = {1-6},
	publisher = {IEEE},
	organization = {IEEE},
	address = {Banff (Canad{\'a})},
	isbn = { 978-1-4673-8401-8},
	author = {Gualda, D and Ure{\~n}a, J. and JC. Garc{\'\i}a and E. Garc{\'\i}a and FJ. Alvarez}
}
