The study focused on unique isotopic signatures of methane from different sources. (insideclimatenews.org)
On the AAE 2013 - 2014 we undertook to map the stable isotopic signatures in seals to investigate whether there has been a change in diet over time. (spiritofmawson.com)
The probability that the impactor just happened to have the same isotopic signature as Earth was vanishingly small. (sciencedaily.com)