Royalty-free licenses let you pay once to use copyrighted images and video clips in personal and commercial projects on an ongoing basis without requiring additional payments each time you use that ...

• 0.02‒41% C transfers are from a donor to a receiver, but< 10% in the reverse route • 0.04‒80% N transfers are from a donor to a receiver, but< 15% in the reverse route Figure 1 Milestones in ...

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