There are 2 matches

Collection Authorizer Collection name Reference
18063J. Alroy Big Spring Canyon (= UCMP V-3322; SDSM V-512; Ed Ross Ranch) Clarendonian - South Dakota Gregory (1942)
18268J. Alroy Mission (= SDSM V-5314; Thomas Fox Ranch; Joe Thin Elk Gravel Pits) Clarendonian - South Dakota Green (1971)

Do another search