MLA

Arnaboldi, Valerio, et al. Online Social Networks : Human Cognitive Constraints In Facebook and Twitter Personal Graphs. Elsevier, 2015.

APA

Arnaboldi, V., Conti, M., Dunbar, R. Ian MacDonald, Passarella, A., & Dunbar, R. I. M. (2015). Online Social Networks : Human Cognitive Constraints in Facebook and Twitter Personal Graphs. Elsevier.

Chicago

Arnaboldi, Valerio, Marco Conti, Robin Ian MacDonald Dunbar, Andrea Passarella, and Robin I. M Dunbar. Online Social Networks : Human Cognitive Constraints In Facebook and Twitter Personal Graphs. : Elsevier, 2015.