Classification of Mammals by Malcolm C. McKenna and Susan K. Bell (page 149)

Classification of Mammals: Above the Species Level (subscription required).

Classification of Mammals above the species level.

McKenna MC & Bell SK (1997), Classification of Mammals Above the Species Level.

The list follows McKenna and Bells Classification of Mammals for prehistoric genera (1997).

McKenna, M.C. & Bell, S.K. Classification of Mammals Above the Species Level.

Classification of Mammals above the Species Level.

They were introduced more widely by the biologist George G. Simpson in his 1945 work "The Principles of Classification and a Classification of Mammals."

Classification of Mammals: Above the species level.