"Sources and methods" seems to be an official CIA/NSA terminology to talk about the main categories things that whistleblowers were not supposed to whistleblow.
The term is more broadly used however outside of the NSA, e.g. it is also present on this website which talks about the CIA 2010 covert communication websites fiasco.
Figure 1.
Edward Snowden in 2013
. Source. From the film Prism, during interview with reporter Glenn Greenwald.
Video 1.
Edward Snowden original interview cut by The Guardian (2013)
Source.
Video 1.
Snowden Opens Up About His Girlfriend
. Source. TODO interviewed by.
Video 2.
"Citizenfour" winning Best Documentary Feature by Oscars (2014)
Source. Lindsay attended.
Video 1.
Aptitude test scene from the Snowden 2016 film
. Source.
Video 2.
FISA Court Order The Guardian discussion scene from the Snowden 2016 film
. Source.
Video 3.
How is this Possible? scene from the Snowden 2016 film
. Source.
Video 4.
Fresh Brains for You scene from the Snowden 2016 film
. Source.

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