Gill, R. T. (1967). Economic development: Past and present. Prentice-Hall.
Lua i Stíl Chicago (17ú heag.)Gill, Richard T. Economic Development: Past and Present. Englewood Cliffs, NJ: Prentice-Hall, 1967.
Lua MLA (9ú heag.)Gill, Richard T. Economic Development: Past and Present. Prentice-Hall, 1967.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.