1997 IUCN red list of threatened plants (1997)

Atti della Reale Accademia delle scienze di Torino - Reale accademia delle scienze di Torino (L'Accademia, 1886)

Index Kewensis. names of seed-bearing plants at the rank of family and below published between January 1976 and the end of 1980 with some omissions from earlier years Supplement seventeen - Royal Botanic Gardens, Kew. (Clarendon Press)

List of rare, threatened and endemic plants in Europe (1982 edition) (1983)

Preliminary draft list of plant species for inclusion in a 'Responsibility List' of European plants - WCMC (WCMC, 1989)

Quarterly summary of re-identifications, January, February, March 1962 : Summary No. 8 - United States. Bureau of Plant Industry, (New Crops Research Branch, Plant Industry Station, 1960)

Summary of re-identifications - December 1959 through June 1960 : Change No. 1 - United States. Agricultural Research Service. New Crops Research Branch, (New Crops Research Branch, 1960)

Summary of re-identifications - December 1959 through June 1960 : Change No. 1 - United States. Agricultural Research Service. New Crops Research Branch, (New Crops Research Branch, 1960)