If you've acquired references from multiple sources, you'll want to check to make sure that you aren't keeping multiple copies of the same reference.
From the pull-down menu labeled "References", select the option labeled "Find Duplicates".
The software offers you a choice of which form of the referene to keep.
When you've decided which reference to keep, click on the button labeled "Keep this Record".
To add references to a group, click on them once to highlight them.
Froom the pull-down menu labeled "Groups", select the option labeled "Add References To".
If you already have existing groups, select the group you want to add the references to.
If you have no existing groups, or if you want to create a new group for these references, select the option labeled "Creat Custom Group".
If you are creating a group for the first time, you will need to give the group a name.
Be sure to give your group a meaningful name. "Cholera vaccines" is more meaningful thatn "PubMed Search".