Search for "cyclic (alkyl) (amino) carbenes" in Full Text gives 3 result(s) in Beilstein Journal of Organic Chemistry.
Beilstein J. Org. Chem. 2023, 19, 1947–1956, doi:10.3762/bjoc.19.145
Beilstein J. Org. Chem. 2018, 14, 3122–3149, doi:10.3762/bjoc.14.292
Beilstein J. Org. Chem. 2010, 6, 709–712, doi:10.3762/bjoc.6.82