@inproceedings{deluca2014,
 author = {De Luca,, Alexander and Harbach,, Marian and von Zezschwitz,, Emanuel and Maurer,, Max-Emanuel and Slawik,, Bernhard Ewald and Hussmann,, Heinrich and Smith,, Matthew},
 title = {Now You See Me, Now You Don't: Protecting Smartphone Authentication from Shoulder Surfers},
 booktitle = {Proceedings of the 32nd Annual ACM Conference on Human Factors in Computing Systems},
 series = {CHI '14},
 year = {2014},
 isbn = {978-1-4503-2473-1},
 location = {Toronto, Ontario, Canada},
 pages = {2937--2946},
 numpages = {10},
 url = {http://doi.acm.org/10.1145/2556288.2557097},
 doi = {10.1145/2556288.2557097},
 acmid = {2557097},
 publisher = {ACM},
 address = {New York, NY, USA},
 keywords = {authentication, back-of-device interaction, security},
}