Search for "artificially expanded genetic information systems" in Full Text gives 2 result(s) in Beilstein Journal of Organic Chemistry.
Beilstein J. Org. Chem. 2014, 10, 2348–2360, doi:10.3762/bjoc.10.245
Beilstein J. Org. Chem. 2014, 10, 1826–1833, doi:10.3762/bjoc.10.192