A 'source' in ReInfer refers to a raw collection of verbatims which can grow over time. For example, a source could be all the responses collected to a survey, the emails in a mailbox, the transcripts in a messaging channel, or all of the calls against a telephone number.
You can add up to 20 sources to a dataset in the GUI.
Please Note: You should only add multiple sources to a dataset if they are of a similar type and share a similar intended purpose (e.g. capturing customer feedback, or multiple email inboxes that service similar requests).
You can see all of the sources in your Re:infer account by navigating to the Sources page.