History of Space Exploration: Chapter 6, Exercise 3 — Possible Solution
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BY WHO COULD CHECK
- Orbital imagery: anyone with the orbiter's published photographs.
- Samples: scientists given access to Moon rocks.
- Soviet tracking: a rival with its own monitoring.
- Retroreflectors: anyone with lasers able to measure them.

NOT SHOWN
The chapter does not give the details of any of these, and I did not read the
article's rebuttals. The Soviet point rests on the article's statement that they
monitored the missions.