||Landenmark HK, Forgan DH, Cockell CS. An Estimate of the Total DNA in the Biosphere. PLoS Biol. 2015 Jun 11 13(6):e1002168. doi: 10.1371/journal.pbio.1002168. p.3/10 bottom paragraphPubMed ID26066900
||DeFlaun MF, Paul JH, Jeffrey WH. Distribution and molecular weight of dissolved DNA in subtropical estuarine and oceanic environments. Mar Ecol Prog Ser. 1987 38(1): 65.
||p.3/10 bottom paragraph:"[Investigators] utilised data on DNA concentrations in soil and water to achieve a much coarser-grained global estimate of the quantity of DNA in the environment. The quantity of dissolved DNA in aquatic environments is of the order of 10 µg/l [primary source] and the total volume of aquatic habitats on Earth is 1.4 × 10^21 l [refs 5,27], giving a total quantity of DNA of approximately 1.4 × 10^31 Mb."