↑USDA, NRCS (n.d.). „Trifolium amoenum“. The PLANTS Database (plants.usda.gov) (enska). Greensboro, North Carolina: National Plant Data Team. Sótt 15. desember 2015.
↑U.S. Federal Register: Proposed Rule, September 11, 1996 (Volume 61, Number 177) [page 47856-47857]