Ижил төстэй зүйлс: The Geographical observer [Geogr Obs] NLMUID: 101095037
- Ethiopia observer [Ethiop Obs] NLMUID: 100967325
- The national observer [Natl Obs] NLMUID: 100972135
- The OECD observer [OECD Obs] NLMUID: 101085063
- APS observer [APS Obs] NLMUID: 101288557
- Observational studies [Obs Stud] NLMUID: 101656496
- Medical facts and observations [Med Facts Obs] NLMUID: 0017416