1
Argitaratua: 1991
Superior document: Working papers / Population Council, Programs Division 5
2
Argitaratua: 1993
Superior document: Working papers / Population Council, Programs Division 6
3
Argitaratua: 1993
Superior document: Working papers / Population Council, Programs Division 7
4
Argitaratua: 2003.
Links: Testu osoa
5
Argitaratua: 2019