A systematic review attempts to find all the empirical evidence to answer a research question.
Examples below -- usually at least 3 databases are searched. Look at similar SRs in Cochrane, etc. to see what's expected.
"Miscellaneous" sources that aren't peer-reviewed articles. May have to adjust search strategy. Think about best gray literature sources for your subject.
Documenting your search:
SR references may be fully handled within Endnote, Zotero, or another reference manager. Excel files may also be used.
Increasingly, SRs are managed within Covidence, Rayyan, or other specialized software. They may be moved here from your reference manager, or references may be exported directly to specialized SR software..