Browse the search results, find what you are looking for and then click Add next to the paper you would like to cite. Need to cite more papers? Keep searching and keep adding. When you're done click Cite and Close. If you want to modify the format of your citation, you can do so by clicking Change Format. Here's an example of what a citation to two papers looks like when formatted in (Author1 et al, year; Author2 et al, year): \citep{Chessa_1999,Stephenson_2014}.