Institute For Scientific Co-operation. (1980). Economics. Laupp & Gobel, Tubingen.
শিকাগো স্টাইল (17 তম সংস্করণ) উদ্ধৃতিInstitute For Scientific Co-operation. Economics. Federal Republic of Germany: Laupp & Gobel, Tubingen, 1980.
M.L.A (9 ম সংস্করণ) উদ্ধৃতিInstitute For Scientific Co-operation. Economics. Laupp & Gobel, Tubingen, 1980.