Berlage, L. (1975). On the mathematics of economic aid. St. Ignatius Faculties.
Lua i Stíl Chicago (17ú heag.)Berlage, L. On the Mathematics of Economic Aid. Antwerp, Belgium: St. Ignatius Faculties, 1975.
Lua MLA (9ú heag.)Berlage, L. On the Mathematics of Economic Aid. St. Ignatius Faculties, 1975.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.