Reason: None provided.
I looked up the "non-radioactive-isotopes" he mentions.
It's a ratio of 2 or more naturally occurring isotopes that can identify where the paper came from by using a map.
2 years ago
1 score
Reason: Original
I looked up the "non-radioactive-isotopes" he mentions.
It's a ratio of 2 or more naturally occurring isotopes that can identify where the paper came from by using a map.
2 years ago
1 score